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Wednesday, October 20, 2021

Free-market anarchism

From Wikipedia, the free encyclopedia
 
Market libertarian socialist mural reading "Free-market, anti-capitalist"

Free-market anarchism, or market anarchism, also known as free-market anti-capitalism and free-market socialism, is the branch of anarchism that advocates a free-market economic system based on voluntary interactions without the involvement of the state. A form of individualist anarchism, left-libertarianism and market socialism, it is based on the economic theories of mutualism and individualist anarchism in the United States. Left-wing market anarchism is a modern branch of free-market anarchism that is based on a revival of such free-market anarchist theories. It is associated with left-libertarians such as Kevin Carson and Gary Chartier, who consider themselves anti-capitalists and socialists.

Samuel Edward Konkin III's agorism is a strand of left-wing market anarchism that has been associated with left-libertarianism in the United States, with counter-economics being its means. Anarcho-capitalism, a form of right-libertarianism, has been occasionally referred to as free-market anarchism or market anarchism, among other names. Anarcho-capitalists stress the legitimacy and priority of private property, without any distinction between personal property and productive property, describing it as an integral component of individual rights and a free-market economy. However, anarcho-capitalism is not considered as part of the anarchist movement because anarchism has historically been an anti-capitalist movement and anarchists reject that it is compatible with capitalism. In addition, an analysis of individualist anarchists who advocated free-market anarchism shows that it is different from anarcho-capitalism and other capitalist theories due to the individualist anarchists retaining the labor theory of value and socialist doctrines.

Free-market anarchism may refer to diverse economic and political concepts like those proposed by individualist anarchists and libertarian socialists such as the Europeans Émile Armand, Thomas Hodgskin, Miguel Giménez Igualada and Pierre-Joseph Proudhon, or the Americans Stephen Pearl Andrews, William Batchelder Greene, Lysander Spooner, Benjamin Tucker and Josiah Warren, among others; and occasionally anarcho-capitalists such as David D. Friedman or various anti-capitalists, left-libertarians and left-wing market anarchists such as Carson, Chartier, Charles W. Johnson, Konkin, Roderick T. Long, Sheldon Richman, Chris Matthew Sciabarra and Brad Spangler.

History

Josiah Warren, the first American anarchist, was an early mutualist

Josiah Warren is widely regarded as the first American anarchist and the four-page weekly paper he edited during 1833, The Peaceful Revolutionist, was the first anarchist periodical published, an enterprise for which he built his own printing press, cast his own type and made his own printing plates. Warren was a follower of Robert Owen and joined Owen's community at New Harmony, Indiana. Josiah Warren termed the phrase "cost the limit of price", with "cost" here referring not to monetary price paid but the labor one exerted to produce an item. Therefore, "he proposed a system to pay people with certificates indicating how many hours of work they did. They could exchange the notes at local time stores for goods that took the same amount of time to produce". He put his theories to the test by establishing an experimental "labor for labor store" called the Cincinnati Time Store where trade was facilitated by notes backed by a promise to perform labor. The store proved successful and operated for three years after which it was closed so that Warren could pursue establishing colonies based on mutualism. These included Utopia and Modern Times. Warren said that Stephen Pearl Andrews' The Science of Society, published in 1852, was the most lucid and complete exposition of Warren's own theories. Catalan historian Xavier Diez report that the intentional communal experiments pioneered by Warren were influential in European individualist anarchists of the late 19th and early 20th centuries such as Émile Armand and the intentional communities started by them.

Mutualism began in 18th-century English and French labour movements before taking an anarchist form associated with Pierre-Joseph Proudhon in France and others in the United States. Proudhon proposed spontaneous order, whereby organisation emerges without central authority, a "positive anarchy" where order arises when everybody does "what he wishes and only what he wishes" and where "business transactions alone produce the social order". It is important to recognize that Proudhon distinguished between ideal political possibilities and practical governance. For this reason, much in contrast to some of his theoretical statements concerning ultimate spontaneous self-governance, Proudhon was heavily involved in French parliamentary politics and allied himself not with Anarchist but Socialist factions of workers movements and in addition to advocating state-protected charters for worker-owned cooperatives, promoted certain nationalization schemes during his life of public service. Mutualist anarchism is concerned with reciprocity, free association, voluntary contract, federation and credit and currency reform. According to the American mutualist William Batchelder Greene, each worker in the mutualist system would receive "just and exact pay for his work; services equivalent in cost being exchangeable for services equivalent in cost, without profit or discount". Mutualism has been retrospectively characterised as ideologically situated between individualist and collectivist forms of anarchism. Proudhon first characterised his goal as a "third form of society, the synthesis of communism and property".

Pierre-Joseph Proudhon, the first self-identified anarchist, supported a free-market anarchist theory called mutualism

Pierre-Joseph Proudhon was a French activist and theorist, the founder of mutualist philosophy, an economist and a libertarian socialist. He was the first person to declare himself an anarchist and is among its most influential theorists. He is considered by many to be the "father of anarchism". He became a member of the French Parliament after the Revolution of 1848, whereupon and thereafter he referred to himself as a federalist. Proudhon, who was born in Besançon, was a printer who taught himself Latin in order to better print books in the language. His best-known assertion is that "property is theft!", contained in his first major work What is Property? Or, an Inquiry into the Principle of Right and Government (Qu'est-ce que la propriété? Recherche sur le principe du droit et du gouvernement), published in 1840. The book's publication attracted the attention of the French authorities. It also attracted the scrutiny of Karl Marx, who started a correspondence with its author. The two influenced each other and met in Paris while Marx was exiled there. Their friendship finally ended when Marx responded to Proudhon's The System of Economic Contradictions, or The Philosophy of Poverty with the provocatively titled The Poverty of Philosophy. The dispute became one of the sources of the split between the anarchist and Marxian wings of the International Workingmen's Association. Some, such as Edmund Wilson, have contended that Marx's attack on Proudhon had its origin in the latter's defense of Karl Grün, whom Marx bitterly disliked but who had been preparing translations of Proudhon's work. Proudhon favored workers' associations or co-operatives as well as individual worker/peasant possession over private ownership or the nationalization of land and workplaces. He considered social revolution to be achievable in a peaceful manner. In The Confessions of a Revolutionary Proudhon asserted that "Anarchy is Order Without Power", the phrase which much later inspired, in the view of some, the anarchist circled-A symbol, today "one of the most common graffiti on the urban landscape". He unsuccessfully tried to create a national bank to be funded by what became an abortive attempt at an income tax on capitalists and shareholders. Similar in some respects to a credit union, it would have given interest-free loans.

William Batchelder Greene was a 19th-century mutualist individualist anarchist, Unitarian minister, soldier and promoter of free banking in the United States. Greene is best known for the works Mutual Banking (1850), which proposed an interest-free banking system; and Transcendentalism, a critique of the New England philosophical school. American anarchist historian Eunice Minette Schuster states: "It is apparent that Proudhonian Anarchism was to be found in the United States at least as early as 1848 and that it was not conscious of its affinity to the Individualist Anarchism of Josiah Warren and Stephen Pearl Andrews. William B. Greene presented this Proudhonian Mutualism in its purest and most systematic form". After 1850, he became active in labor reform and was elected vice-president of the New England Labor Reform League, the majority of the members holding to Proudhon's scheme of mutual banking. In 1869, he was elected president of the Massachusetts Labor Union. Greene then published Socialistic, Mutualistic, and Financial Fragments (1875). He saw mutualism as the synthesis of "liberty and order". His "associationism is checked by individualism. 'Mind your own business,' "Judge not that ye be not judged". Over matters which are purely personal, as for example moral conduct, the individual is sovereign, as well as over that which he himself produces. For this reason he demands "mutuality" in marriage – the equal right of a woman to her own personal freedom and property".

Individualist anarchism in the United States

American individualist anarchist Benjamin Tucker, known for his anarchist journal Liberty, abandoned the natural rights conception of property rights in free-market anarchism for a Stirnerite egoism

A form of individualist anarchism was found in the United States as advocated by the Boston anarchists. Most American Individualist Anarchists advocate mutualism, a libertarian socialist form of market socialism, or a free-market socialist form of classical economics. Individualist anarchists are opposed to property that gives privilege and is exploitative, seeking to "destroy the tyranny of capital, — that is, of property" by mutual credit. Some Boston anarchists, including Benjamin Tucker and Lysander Spooner, identified themselves as socialists, a label often used in the 19th century in the sense of a commitment to improving conditions of the working class (i.e. the labor problem). The Boston anarchists such as Tucker and his followers are also considered socialists due to their opposition to usury. By around the start of the 20th century, the heyday of individualist anarchism had passed, On the other hand, anarchist historian George Woodcock describes Spooner's essays as an "eloquent elaboration" of Josiah Warren and the early American development of Proudhon's ideas and associates his works with that of Stephen Pearl Andrews. Woodcock also reports that both Spooner and Greene had been members of the socialist First International.

American individualist anarchist Benjamin Tucker identified as a socialist and argued that the elimination of what he called the four monopolies, namely the land monopoly, the money and banking monopoly, the monopoly powers conferred by patents and the quasi-monopolistic effects of tariffs, would undermine the power of the wealthy and big business, making possible widespread property ownership and higher incomes for ordinary people, while minimizing the power of would-be bosses and achieving socialist goals without state action. Tucker influenced and interacted with anarchist contemporaries, including Lysander Spooner, Voltairine de Cleyre, Dyer Lum and William Batchelder Greene, who have in various ways influenced later left-libertarian thinking. Kevin Carson characterizes American individualist anarchism by saying: "Unlike the rest of the socialist movement, the individualist anarchists believed that the natural wage of labor in a free market was its product and that economic exploitation could only take place when capitalists and landlords harnessed the power of the state in their interests. Thus, individualist anarchism was an alternative both to the increasing statism of the mainstream socialist movement and to a liberal movement that was moving toward a mere apologetic for the power of big business. Two individualist anarchists who wrote in Benjamin Tucker's Liberty were also important labor organizers of the time. Joseph Labadie and Dyer Lum. Kevin Carson has praised Lum's fusion of individualist laissez-faire economics with radical labor activism as "creative" and described him as "more significant than any in the Boston group".

Some of the American individualist anarchists later in this era such as Benjamin Tucker abandoned natural rights positions and converted to Max Stirner's egoist anarchism. Rejecting the idea of moral rights, Tucker said that there were only two rights, "the right of might" and "the right of contract". He also said after converting to egoist individualism: "In times past it was my habit to talk glibly of the right of man to land. It was a bad habit, and I long ago sloughed it off. Man's only right to land is his might over it". In adopting Stirnerite egoism in 1886, Tucker rejected natural rights which had long been considered the foundation of libertarianism. This rejection galvanized the movement into fierce debates, with the natural rights proponents accusing the egoists of destroying libertarianism itself. So bitter was the conflict that a number of natural rights proponents withdrew from the pages of Liberty in protest even though they had hitherto been among its frequent contributors. Thereafter, Liberty championed egoism although its general content did not change significantly.

Individualist anarchism in Europe

Henry George, whose economic positions known as geoism existed within European individualist anarchism

Geolibertarianism, a libertarian form of Henry George's philosophy called geoism, is considered left-libertarian because it assumes land to be initially owned in common, so that when land is privately appropriated the proprietor pays rent to the community. Geolibertarians generally advocate distributing the land rent to the community via a land value tax as proposed by Henry George and others before him. For this reason, they are often called "single taxers". Fred E. Foldvary coined the term geo-libertarianism in a Land and Liberty article. In the case of geoanarchism, the voluntary form of geolibertarianism as described by Foldvary, rent would be collected by private associations with the opportunity to secede from the rent-sharing community and not receive the community's services.

Similar economic positions also existed within European individualist anarchism. French individualist anarchist Émile Armand shows clearly opposition to capitalism and centralized economies when he said that the individualist anarchist "inwardly he remains refractory – fatally refractory – morally, intellectually, economically (The capitalist economy and the directed economy, the speculators and the fabricators of single are equally repugnant to him.)". He argued for a pluralistic economic logic when he said: "Here and there everything happening – here everyone receiving what they need, there each one getting whatever is needed according to their own capacity. Here, gift and barter – one product for another; there, exchange – product for representative value. Here, the producer is the owner of the product, there, the product is put to the possession of the collectivity".

Spanish individualist anarchist Miguel Giménez Igualada thought that "capitalism is an effect of government; the disappearance of government means capitalism falls from its pedestal vertiginously. That which we call capitalism is not something else but a product of the State, within which the only thing that is being pushed forward is profit, good or badly acquired. And so to fight against capitalism is a pointless task, since be it State capitalism or Enterprise capitalism, as long as Government exists, exploiting capital will exist. The fight, but of consciousness, is against the State". His view on class division and technocracy are as follows: "Since when no one works for another, the profiteer from wealth disappears, just as government will disappear when no one pays attention to those who learned four things at universities and from that fact they pretend to govern men. Big industrial enterprises will be transformed by men in big associations in which everyone will work and enjoy the product of their work. And from those easy as well as beautiful problems anarchism deals with and he who puts them in practice and lives them are anarchists. The priority which without rest an anarchist must make is that in which no one has to exploit anyone, no man to no man, since that non-exploitation will lead to the limitation of property to individual needs".

Alliance between libertarians and the New Left in the United States

The doyen of modern American market-oriented libertarianism, Austrian School economist Murray Rothbard, was initially an enthusiastic partisan of the Old Right, particularly because of its general opposition to war and imperialism. However, Rothbard had long embraced a reading of American history that emphasized the role of elite privilege in shaping legal and political institutions—one that was naturally agreeable to many on the left—and came increasingly in the 1960s to seek alliances on the left—especially with members of the New Left—in light of the Vietnam War, the military draft and the emergence of the Black Power movement.

Working with other likeminded people like Ronald Radosh and Karl Hess, Rothbard argued that the consensus view of American economic history, according to which a beneficent government has used its power to counter corporate predation, is fundamentally flawed. Rather, he argued, government intervention in the economy has largely benefited established players at the expense of marginalized groups, to the detriment of both liberty and equality. Moreover, the robber baron period, hailed by the right and despised by the left as a heyday of laissez-faire, was not characterized by laissez-faire at all, but it was in fact a time of massive state privilege accorded to capital. In tandem with his emphasis on the intimate connection between state and corporate power, he defended the seizure of corporations dependent on state largesse by workers and others.

Rothbard himself ultimately broke with the left, allying himself instead with the burgeoning paleoconservative movement. Drawing on the work of Rothbard during his alliance with the left and on the thought of Karl Hess, some thinkers associated with market-oriented American libertarianism came increasingly to identify with the left on a range of issues, including opposition to war, to corporate oligopolies and to state-corporate partnerships as well as an affinity for cultural liberalism. One variety of this kind of libertarianism has been a resurgent mutualism, incorporating modern economic ideas such as marginal utility theory into mutualist theory. Kevin Carson's Studies in Mutualist Political Economy helped to stimulate the growth of new-style mutualism, articulating a version of the labor theory of value incorporating ideas drawn from Austrian economics. Other market-oriented left-libertarians have declined to embrace mutualist views of real property while sharing the mutualist opposition to corporate hierarchies and wealth concentration. Left-libertarians have placed particular emphasis on the articulation and defense of a libertarian theory of class and class conflict, although considerable work in this area has been performed by libertarians of other persuasions.

Left-wing market anarchism

Left-wing market anarchism is a contemporary school of left-libertarianism and a revival of the free-market anarchist theories of mutualism and 19th century individualist anarchism. It is associated with scholars such as Kevin Carson, Gary Chartier, Charles W. Johnson, Samuel Edward Konkin III, Roderick T. Long, Sheldon Richman,  Chris Matthew Sciabarra and Brad Spangler, who stress the value of radically free markets, termed freed markets to distinguish them from the common conception which these libertarians believe to be riddled with statist and capitalist privileges. Referred to as left-wing market anarchists, market-oriented or free-market left-libertarians, proponents of this approach distinguish themselves from right-libertarians and strongly affirm the classical liberal ideas of self-ownership and free markets while maintaining that taken to their logical conclusions these ideas support strongly anti-capitalist, anti-corporatist, anti-hierarchical and pro-labor positions in economics; anti-imperialism in foreign policy; and thoroughly liberal or radical views regarding issues such as class, gender, sexuality and race. This strand of left-libertarianism tends to be rooted either in the mutualist economics conceptualized by Pierre-Joseph Proudhon, American individualist anarchism, or in a left-wing interpretation or extension of the thought of Murray Rothbard. These left-libertarians rejects "what critics call "atomistic individualism". With freed markets, they argue that "it is we collectively who decide who controls the means of production", leading to "a society in which free, voluntary, and peaceful cooperation ultimately controls the means of production for the good of all people".

According to libertarian scholar Sheldon Richman, left-libertarians "favor worker solidarity vis-à-vis bosses, support poor people's squatting on government or abandoned property, and prefer that corporate privileges be repealed before the regulatory restrictions on how those privileges may be exercised", seeing Walmart as a "symbol of corporate favoritism" which is "supported by highway subsidies and eminent domain", viewing "the fictive personhood of the limited-liability corporation with suspicion" and "doubt[ing] that Third World sweatshops would be the "best alternative" in the absence of government manipulation". These left-libertarians "tend to eschew electoral politics, having little confidence in strategies that work through the government. They prefer to develop alternative institutions and methods of working around the state".

Gary Chartier has joined Kevin Carson, Charles W. Johnson and others (echoing the language of Stephen Pearl Andrews, William Batchelder Greene, Thomas Hodgskin, Pierre-Joseph Proudhon, Lysander Spooner, Benjamin Tucker and Josiah Warren, among others) in maintaining that because of its heritage and its emancipatory goals and potential, radical market anarchism should be seen by its proponents and by others as part of the socialist tradition and that market anarchists can and should call themselves socialists.

Forms of geolibertarianism also fit into this group, but these geoists are less likely to accept terms such as anti-capitalist or socialist. While adopting familiar libertarian views, including opposition to civil liberties violations, drug prohibition, gun control, imperialism and war, left-libertarians are more likely than most self-identified libertarians to take more distinctively leftist stances on issues as diverse as class, egalitarianism, environmentalism, feminism, gender, immigration, race, sexuality and war. Contemporary free-market left-libertarians show markedly more sympathy than American mainstream libertarians or paleolibertarians towards various cultural movements which challenge non-governmental relations of power. Left-libertarians such as Long and Johnson have called for a recovery of the 19th-century alliance with libertarian feminism and radical liberalism.

Especially influential regarding these topics have been scholars including Long, Johnson, Sciabarra and Arthur Silber. The genealogy of contemporary market-oriented left-libertarianism, sometimes labeled left-wing market anarchism, overlaps to a significant degree with that of Steiner–Vallentyne left-libertarianism as the roots of that tradition are sketched in The Origins of Left-Libertarianism. Carson–Long-style left-libertarianism is rooted in 19th-century mutualism and in the work of figures such as the British Thomas Hodgskin and Anarchists within American individualist anarchism such as Benjamin Tucker and Lysander Spooner. While with notable exceptions market-oriented libertarians after Tucker tended to ally with the political right, relationships between such libertarians and the New Left thrived in the 1960s, laying the groundwork for modern left-wing market anarchism.

The Really Really Free Market movement is a horizontally organized collective of individuals who form a temporary market based on an alternative gift economy. The movement aims to counteract capitalism in a proactive way by creating a positive example to challenge the myths of scarcity and competition. The name itself is a play on words as it is a reinterpretation and re-envisioning of free market, a term which generally refers to an economy of consumerism governed by supply and demand.

Criticism

David McNally of the University of Houston argues in the Marxist tradition that the logic of the market inherently produces inequitable outcomes and leads to unequal exchanges, arguing that Adam Smith's moral intent and moral philosophy espousing equal exchange was undermined by the practice of the free market he championed. According to McNally, the development of the market economy involved coercion, exploitation and violence that Smith's moral philosophy could not countenance. McNally criticizes free-market anarchism and other market socialists for believing in the possibility of fair markets based on equal exchanges to be achieved by purging parasitical elements from the market economy such as private ownership of the means of production, arguing that market socialism is an oxymoron when socialism is defined as an end to wage labour.

Tuesday, October 19, 2021

Cellulose

From Wikipedia, the free encyclopedia

Cellulose, a linear polymer of D-glucose units (two are shown) linked by β(1→4)-glycosidic bonds
Three-dimensional structure of cellulose
Identifiers
  • 9004-34-6 check
ChEMBL
ChemSpider
  • None
ECHA InfoCard 100.029.692 Edit this at Wikidata
EC Number
  • 232-674-9
E number E460 (thickeners, ...)
UNII
Properties
(C
6
H
10
O
5
)
n
Molar mass 162.1406 g/mol per glucose unit
Appearance white powder
Density 1.5 g/cm3
Melting point 260–270 °C; 500–518 °F; 533–543 K Decomposes
none
Thermochemistry
−963,000 kJ/mol
−2828,000 kJ/mol
Hazards
NFPA 704 (fire diamond)
1
1
0
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 15 mg/m3 (total) TWA 5 mg/m3 (resp)
REL (Recommended)
TWA 10 mg/m3 (total) TWA 5 mg/m3 (resp)
IDLH (Immediate danger)
N.D.
Related compounds
Related compounds
Starch
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Cellulose is an organic compound with the formula (C
6
H
10
O
5
)
n
, a polysaccharide consisting of a linear chain of several hundred to many thousands of β(1→4) linked D-glucose units. Cellulose is an important structural component of the primary cell wall of green plants, many forms of algae and the oomycetes. Some species of bacteria secrete it to form biofilms. Cellulose is the most abundant organic polymer on Earth. The cellulose content of cotton fiber is 90%, that of wood is 40–50%, and that of dried hemp is approximately 57%.

Cellulose is mainly used to produce paperboard and paper. Smaller quantities are converted into a wide variety of derivative products such as cellophane and rayon. Conversion of cellulose from energy crops into biofuels such as cellulosic ethanol is under development as a renewable fuel source. Cellulose for industrial use is mainly obtained from wood pulp and cotton.

Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic micro-organisms that live in their guts, such as Trichonympha. In human nutrition, cellulose is a non-digestible constituent of insoluble dietary fiber, acting as a hydrophilic bulking agent for feces and potentially aiding in defecation.

History

Cellulose was discovered in 1838 by the French chemist Anselme Payen, who isolated it from plant matter and determined its chemical formula. Cellulose was used to produce the first successful thermoplastic polymer, celluloid, by Hyatt Manufacturing Company in 1870. Production of rayon ("artificial silk") from cellulose began in the 1890s and cellophane was invented in 1912. Hermann Staudinger determined the polymer structure of cellulose in 1920. The compound was first chemically synthesized (without the use of any biologically derived enzymes) in 1992, by Kobayashi and Shoda.

The arrangement of cellulose and other polysaccharides in a plant cell wall.

Structure and properties

Cellulose under a microscope.

Cellulose has no taste, is odorless, is hydrophilic with the contact angle of 20–30 degrees, is insoluble in water and most organic solvents, is chiral and is biodegradable. It was shown to melt at 467 °C in pulse tests made by Dauenhauer et al. (2016). It can be broken down chemically into its glucose units by treating it with concentrated mineral acids at high temperature.

Cellulose is derived from D-glucose units, which condense through β(1→4)-glycosidic bonds. This linkage motif contrasts with that for α(1→4)-glycosidic bonds present in starch and glycogen. Cellulose is a straight chain polymer. Unlike starch, no coiling or branching occurs and the molecule adopts an extended and rather stiff rod-like conformation, aided by the equatorial conformation of the glucose residues. The multiple hydroxyl groups on the glucose from one chain form hydrogen bonds with oxygen atoms on the same or on a neighbor chain, holding the chains firmly together side-by-side and forming microfibrils with high tensile strength. This confers tensile strength in cell walls where cellulose microfibrils are meshed into a polysaccharide matrix. The high tensile strength of plant stems and of the tree wood also arises from the arrangement of cellulose fibers intimately distributed into the lignin matrix. The mechanical role of cellulose fibers in the wood matrix responsible for its strong structural resistance, can somewhat be compared to that of the reinforcement bars in concrete, lignin playing here the role of the hardened cement paste acting as the "glue" in between the cellulose fibers. Mechanical properties of cellulose in primary plant cell wall are correlated with growth and expansion of plant cells. Live fluorescence microscopy techniques are promising in investigation of the role of cellulose in growing plant cells.

A triple strand of cellulose showing the hydrogen bonds (cyan lines) between glucose strands
 
Cotton fibres represent the purest natural form of cellulose, containing more than 90% of this polysaccharide.

Compared to starch, cellulose is also much more crystalline. Whereas starch undergoes a crystalline to amorphous transition when heated beyond 60–70 °C in water (as in cooking), cellulose requires a temperature of 320 °C and pressure of 25 MPa to become amorphous in water.

Several types of cellulose are known. These forms are distinguished according to the location of hydrogen bonds between and within strands. Natural cellulose is cellulose I, with structures Iα and Iβ. Cellulose produced by bacteria and algae is enriched in Iα while cellulose of higher plants consists mainly of Iβ. Cellulose in regenerated cellulose fibers is cellulose II. The conversion of cellulose I to cellulose II is irreversible, suggesting that cellulose I is metastable and cellulose II is stable. With various chemical treatments it is possible to produce the structures cellulose III and cellulose IV.

Many properties of cellulose depend on its chain length or degree of polymerization, the number of glucose units that make up one polymer molecule. Cellulose from wood pulp has typical chain lengths between 300 and 1700 units; cotton and other plant fibers as well as bacterial cellulose have chain lengths ranging from 800 to 10,000 units. Molecules with very small chain length resulting from the breakdown of cellulose are known as cellodextrins; in contrast to long-chain cellulose, cellodextrins are typically soluble in water and organic solvents.

The chemical formula of cellulose is (C6H10O5)n where n is the degree of polymerization and represents the number of glucose groups.

Plant-derived cellulose is usually found in a mixture with hemicellulose, lignin, pectin and other substances, while bacterial cellulose is quite pure, has a much higher water content and higher tensile strength due to higher chain lengths.

Cellulose consists of fibrils with crystalline and amorphous regions. These cellulose fibrils may be individualized by mechanical treatment of cellulose pulp, often assisted by chemical oxidation or enzymatic treatment, yielding semi-flexible cellulose nanofibrils generally 200 nm to 1 μm in length depending on the treatment intensity. Cellulose pulp may also be treated with strong acid to hydrolyze the amorphous fibril regions, thereby producing short rigid cellulose nanocrystals a few 100 nm in length. These nanocelluloses are of high technological interest due to their self-assembly into cholesteric liquid crystals, production of hydrogels or aerogels, use in nanocomposites with superior thermal and mechanical properties, and use as Pickering stabilizers for emulsions.

Processing

Biosynthesis

In plants cellulose is synthesized at the plasma membrane by rosette terminal complexes (RTCs). The RTCs are hexameric protein structures, approximately 25 nm in diameter, that contain the cellulose synthase enzymes that synthesise the individual cellulose chains. Each RTC floats in the cell's plasma membrane and "spins" a microfibril into the cell wall.

RTCs contain at least three different cellulose synthases, encoded by CesA (Ces is short for "cellulose synthase") genes, in an unknown stoichiometry. Separate sets of CesA genes are involved in primary and secondary cell wall biosynthesis. There are known to be about seven subfamilies in the plant CesA superfamily, some of which include the more cryptic, tentatively-named Csl (cellulose synthase-like) enzymes. These cellulose syntheses use UDP-glucose to form the β(1→4)-linked cellulose.

Bacterial cellulose is produced using the same family of proteins, although the gene is called BcsA for "bacterial cellulose synthase" or CelA for "cellulose" in many instances. In fact, plants acquired CesA from the endosymbiosis event that produced the chloroplast. All cellulose synthases known belongs to glucosyltransferase family 2 (GT2).

Cellulose synthesis requires chain initiation and elongation, and the two processes are separate. Cellulose synthase (CesA) initiates cellulose polymerization using a steroid primer, sitosterol-beta-glucoside, and UDP-glucose. It then utilizes UDP-D-glucose precursors to elongate the growing cellulose chain. A cellulase may function to cleave the primer from the mature chain.

Cellulose is also synthesised by tunicate animals, particularly in the tests of ascidians (where the cellulose was historically termed "tunicine" (tunicin)).

Breakdown (cellulolysis)

Cellulolysis is the process of breaking down cellulose into smaller polysaccharides called cellodextrins or completely into glucose units; this is a hydrolysis reaction. Because cellulose molecules bind strongly to each other, cellulolysis is relatively difficult compared to the breakdown of other polysaccharides. However, this process can be significantly intensified in a proper solvent, e.g. in an ionic liquid.

Most mammals have limited ability to digest dietary fiber such as cellulose. Some ruminants like cows and sheep contain certain symbiotic anaerobic bacteria (such as Cellulomonas and Ruminococcus spp.) in the flora of the rumen, and these bacteria produce enzymes called cellulases that hydrolyze cellulose. The breakdown products are then used by the bacteria for proliferation. The bacterial mass is later digested by the ruminant in its digestive system (stomach and small intestine). Horses use cellulose in their diet by fermentation in their hindgut. Some termites contain in their hindguts certain flagellate protozoa producing such enzymes, whereas others contain bacteria or may produce cellulase.

The enzymes used to cleave the glycosidic linkage in cellulose are glycoside hydrolases including endo-acting cellulases and exo-acting glucosidases. Such enzymes are usually secreted as part of multienzyme complexes that may include dockerins and carbohydrate-binding modules.

Breakdown (thermolysis)

At temperatures above 350 °C, cellulose undergoes thermolysis (also called 'pyrolysis'), decomposing into solid char, vapors, aerosols, and gases such as carbon dioxide. Maximum yield of vapors which condense to a liquid called bio-oil is obtained at 500 °C.

Semi-crystalline cellulose polymers react at pyrolysis temperatures (350–600 °C) in a few seconds; this transformation has been shown to occur via a solid-to-liquid-to-vapor transition, with the liquid (called intermediate liquid cellulose or molten cellulose) existing for only a fraction of a second. Glycosidic bond cleavage produces short cellulose chains of two-to-seven monomers comprising the melt. Vapor bubbling of intermediate liquid cellulose produces aerosols, which consist of short chain anhydro-oligomers derived from the melt.

Continuing decomposition of molten cellulose produces volatile compounds including levoglucosan, furans, pyrans, light oxygenates and gases via primary reactions. Within thick cellulose samples, volatile compounds such as levoglucosan undergo 'secondary reactions' to volatile products including pyrans and light oxygenates such as glycolaldehyde.

Hemicellulose

Hemicelluloses are polysaccharides related to cellulose that comprise about 20% of the biomass of land plants. In contrast to cellulose, hemicelluloses are derived from several sugars in addition to glucose, especially xylose but also including mannose, galactose, rhamnose, and arabinose. Hemicelluloses consist of shorter chains – between 500 and 3000 sugar units. Furthermore, hemicelluloses are branched, whereas cellulose is unbranched.

Regenerated cellulose

Cellulose is soluble in several kinds of media, several of which are the basis of commercial technologies. These dissolution process is reversible and are used in the production of regenerated celluloses (such as viscose and cellophane) from dissolving pulp.

The most important solubilizing agent is carbon disulfide in the presence of alkali. Other agents include Schweizer's reagent, N-methylmorpholine N-oxide, and lithium chloride in dimethylacetamide. In general these agents modify the cellulose, rendering it soluble. The agents are then removed concomitant with the formation of fibers. Cellulose is also soluble in many kinds of ionic liquids.

The history of regenerated cellulose is often cited as beginning with George Audemars, who first manufactured regenerated nitrocellulose fibers in 1855. Although these fibers were soft and strong -resembling silk- they had the drawback of being highly flammable. Hilaire de Chardonnet perfected production of nitrocellulose fibers, but manufacturing of these fibers by his process was relatively uneconomical. In 1890, L.H. Despeissis invented the cuprammonium process – which uses a cuprammonium solution to solubilize cellulose – a method still used today for production of artificial silk. In 1891, it was discovered that treatment of cellulose with alkali and carbon disulfide generated a soluble cellulose derivative known as viscose. This process, patented by the founders of the Viscose Development Company, is the most widely used method for manufacturing regenerated cellulose products. Courtaulds purchased the patents for this process in 1904, leading to significant growth of viscose fiber production. By 1931, expiration of patents for the viscose process led to its adoption worldwide. Global production of regenerated cellulose fiber peaked in 1973 at 3,856,000 tons.

Regenerated cellulose can be used to manufacture a wide variety of products. While the first application of regenerated cellulose was as a clothing textile, this class of materials is also used in the production of disposable medical devices as well as fabrication of artificial membranes.

Cellulose esters and ethers

The hydroxyl groups (−OH) of cellulose can be partially or fully reacted with various reagents to afford derivatives with useful properties like mainly cellulose esters and cellulose ethers (−OR). In principle, although not always in current industrial practice, cellulosic polymers are renewable resources.

Ester derivatives include:

Cellulose ester Reagent Example Reagent Group R
Organic esters Organic acids Cellulose acetate Acetic acid and acetic anhydride H or −(C=O)CH3
Cellulose triacetate Acetic acid and acetic anhydride −(C=O)CH3
Cellulose propionate Propionic acid H or −(C=O)CH2CH3
Cellulose acetate propionate (CAP) Acetic acid and propanoic acid H or −(C=O)CH3 or −(C=O)CH2CH3
Cellulose acetate butyrate (CAB) Acetic acid and butyric acid H or −(C=O)CH3 or −(C=O)CH2CH2CH3
Inorganic esters Inorganic acids Nitrocellulose (cellulose nitrate) Nitric acid or another powerful nitrating agent H or −NO2
Cellulose sulfate Sulfuric acid or another powerful sulfuring agent H or −SO3H

The cellulose acetate and cellulose triacetate are film- and fiber-forming materials that find a variety of uses. The nitrocellulose was initially used as an explosive and was an early film forming material. With camphor, nitrocellulose gives celluloid.

The sodium carboxymethyl cellulose can be cross-linked to give the croscarmellose sodium (E468) for use as a disintegrant in pharmaceutical formulations.

Commercial applications

A strand of cellulose (conformation Iα), showing the hydrogen bonds (dashed) within and between cellulose molecules.
 

Cellulose for industrial use is mainly obtained from wood pulp and from cotton.

  • Paper products: Cellulose is the major constituent of paper, paperboard, and card stock. Electrical insulation paper: Cellulose is used in diverse forms as insulation in transformers, cables, and other electrical equipment.
  • Fibers: Cellulose is the main ingredient of textiles. Cotton and synthetics (nylons) each have about 40% market by volume. Other plant fibers (jute, sisal, hemp) represent about 20% of the market. Rayon, cellophane and other "regenerated cellulose fibers" are a small portion (5%).
  • Consumables: Microcrystalline cellulose (E460i) and powdered cellulose (E460ii) are used as inactive fillers in drug tablets and a wide range of soluble cellulose derivatives, E numbers E461 to E469, are used as emulsifiers, thickeners and stabilizers in processed foods. Cellulose powder is, for example, used in processed cheese to prevent caking inside the package. Cellulose occurs naturally in some foods and is an additive in manufactured foods, contributing an indigestible component used for texture and bulk, potentially aiding in defecation.
  • Building material: Hydroxyl bonding of cellulose in water produces a sprayable, moldable material as an alternative to the use of plastics and resins. The recyclable material can be made water- and fire-resistant. It provides sufficient strength for use as a building material. Cellulose insulation made from recycled paper is becoming popular as an environmentally preferable material for building insulation. It can be treated with boric acid as a fire retardant.
  • Miscellaneous: Cellulose can be converted into cellophane, a thin transparent film. It is the base material for the celluloid that was used for photographic and movie films until the mid-1930s. Cellulose is used to make water-soluble adhesives and binders such as methyl cellulose and carboxymethyl cellulose which are used in wallpaper paste. Cellulose is further used to make hydrophilic and highly absorbent sponges. Cellulose is the raw material in the manufacture of nitrocellulose (cellulose nitrate) which is used in smokeless gunpowder.
  • Pharmaceuticals: Cellulose derivatives, such as microcrystalline cellulose (MCC), have the advantages of retaining water, being a stabilizer and thickening agent, and in reinforcement of drug tablets.

Aspirational

Energy crops:

The major combustible component of non-food energy crops is cellulose, with lignin second. Non-food energy crops produce more usable energy than edible energy crops (which have a large starch component), but still compete with food crops for agricultural land and water resources. Typical non-food energy crops include industrial hemp, switchgrass, Miscanthus, Salix (willow), and Populus (poplar) species. A strain of Clostridium bacteria found in zebra dung, can convert nearly any form of cellulose into butanol fuel.

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