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62-478: The institute conducts research in polymer science , materials chemistry , and hydrocarbon chemistry. 34°01′09″N 118°17′15″W  /  34.0193°N 118.2874°W  / 34.0193; -118.2874 This article relating to education in the United States is a stub . You can help Misplaced Pages by expanding it . Polymer science Polymer science or macromolecular science

124-401: A bave . Bave diameters for tussah silk can reach 65 μm. See cited reference for cross-sectional SEM photographs. Silk has a smooth, soft texture that is not slippery, unlike many synthetic fibers . Silk is one of the strongest natural fibers, but it loses up to 20% of its strength when wet. It has a good moisture regain of 11%. Its elasticity is moderate to poor: if elongated even

186-474: A Professor of Analytical Chemistry had once said that "although the scarcity of education in polymer science is slowly diminishing but it is still evident in many areas. What is most unfortunate is that it appears to exist, not because of a lack of awareness but, rather, a lack of interest." 2005 (Chemistry) Robert Grubbs , Richard Schrock , Yves Chauvin for olefin metathesis. 2002 (Chemistry) John Bennett Fenn , Koichi Tanaka , and Kurt Wüthrich for

248-424: A large satin waistcoat with flaps, were got up, of which the silk was perfect, but the lining entirely gone ... from the thread giving way ... No articles of dress of woollen cloth have yet been found.' Silk is a poor conductor of electricity and thus susceptible to static cling . Silk has a high emissivity for infrared light, making it feel cool to the touch. Unwashed silk chiffon may shrink up to 8% due to

310-738: A long history of a formative textile industry in ancient China, this find of silk textiles employing "complicated techniques" of weaving and dyeing provides direct evidence for silks dating before the Mawangdui -discovery and other silks dating to the Han dynasty (202 BC – 220 AD). Silk is described in a chapter of the Fan Shengzhi shu from the Western Han (202 BC – 9 AD). There is a surviving calendar for silk production in an Eastern Han (25–220 AD) document. The two other known works on silk from

372-440: A number of small firms and cooperatives emerged. Among the most prominent of these was the cooperative utopian Northampton Association for Education and Industry, of which Sojourner Truth was a member. Following the destructive Mill River Flood of 1874 , one manufacturer, William Skinner , relocated his mill from Williamsburg to the then-new city of Holyoke . Over the next 50 years he and his sons would maintain relations between

434-417: A small amount, it remains stretched. It can be weakened if exposed to too much sunlight. It may also be attacked by insects, especially if left dirty. One example of the durable nature of silk over other fabrics is demonstrated by the recovery in 1840 of silk garments from a wreck of 1782 : 'The most durable article found has been silk; for besides pieces of cloaks and lace, a pair of black satin breeches, and

496-416: A white-colored silk thread with no mineral on the surface. The pupae are killed by either dipping them in boiling water before the adult moths emerge or by piercing them with a needle. These factors all contribute to the ability of the whole cocoon to be unravelled as one continuous thread, permitting a much stronger cloth to be woven from the silk. Wild silks also tend to be more difficult to dye than silk from

558-478: Is a subfield of materials science concerned with polymers , primarily synthetic polymers such as plastics and elastomers . The field of polymer science includes researchers in multiple disciplines including chemistry , physics , and engineering . This science comprises three main sub-disciplines: The first modern example of polymer science is Henri Braconnot 's work in the 1830s. Henri, along with Christian Schönbein and others, developed derivatives of

620-509: Is composed mostly of beta-sheets , due to a 59-mer amino acid repeat sequence with some variations. The flat surfaces of the fibrils reflect light at many angles, giving silk a natural sheen. The cross-section from other silkworms can vary in shape and diameter: crescent-like for Anaphe and elongated wedge for tussah . Silkworm fibers are naturally extruded from two silkworm glands as a pair of primary filaments (brin), which are stuck together, with sericin proteins that act like glue , to form

682-547: Is concentrated in the Coimbatore , Erode , Bhagalpuri , Tiruppur , Salem , and Dharmapuri districts. Hyderabad , Andhra Pradesh , and Gobichettipalayam , Tamil Nadu , were the first locations to have automated silk reeling units in India. In the northeastern state of Assam , three different types of indigenous variety of silk are produced, collectively called Assam silk : Muga silk , Eri silk and Pat silk . Muga,

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744-401: Is due to the triangular prism -like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles , thus producing different colors. Silk is produced by several insects; but, generally, only the silk of moth caterpillars has been used for textile manufacturing. There has been some research into other types of silk, which differ at the molecular level. Silk

806-509: Is forbidden. Modern attire has raised a number of issues, including, for instance, the permissibility of wearing silk neckties , which are masculine articles of clothing. In the Odyssey , 19.233, when Odysseus, while pretending to be someone else, is questioned by Penelope about her husband's clothing, he says that he wore a shirt "gleaming like the skin of a dried onion" (varies with translations, literal translation here) which could refer to

868-649: Is mainly produced by the larvae of insects undergoing complete metamorphosis , but some insects, such as webspinners and raspy crickets , produce silk throughout their lives. Silk production also occurs in hymenoptera ( bees , wasps , and ants ), silverfish , caddisflies , mayflies , thrips , leafhoppers , beetles , lacewings , fleas , flies , and midges . Other types of arthropods produce silk, most notably various arachnids , such as spiders . The word silk comes from Old English : sioloc , from Latin : sericum and Ancient Greek : σηρικός , romanized :  sērikós , "silken", ultimately from

930-584: Is now part of Malaysia , a second generation of silkworm was being imported as early as 1764 for the country's silk textile industry, especially songket . However, since the 1980s, Malaysia is no longer engaged in sericulture but does plant mulberry trees. In Vietnamese legend, silk appeared in the first millennium AD and is still being woven today. The process of silk production is known as sericulture . The entire production process of silk can be divided into several steps which are typically handled by different entities. Extracting raw silk starts by cultivating

992-531: Is potentially large when compared with other natural fibers. A life-cycle assessment of Indian silk production shows that the production process has a large carbon and water footprint, mainly due to the fact that it is an animal-derived fiber and more inputs such as fertilizer and water are needed per unit of fiber produced. Silk fibers from the Bombyx mori silkworm have a triangular cross section with rounded corners, 5–10  μm wide. The fibroin-heavy chain

1054-415: Is soaked in extremely cold water and bleached before dyeing to remove the natural yellow coloring of Thai silk yarn. To do this, skeins of silk thread are immersed in large tubs of hydrogen peroxide . Once washed and dried, the silk is woven on a traditional hand-operated loom. The Rajshahi Division of northern Bangladesh is the hub of the country's silk industry. There are three types of silk produced in

1116-594: Is the presence of the silk protein fibroin in soil samples from two tombs at the neolithic site Jiahu in Henan , which date back about 8,500 years. The earliest surviving example of silk fabric dates from about 3630 BC, and was used as the wrapping for the body of a child at a Yangshao culture site in Qingtaicun near Xingyang , Henan. Legend gives credit for developing silk to a Chinese empress, Leizu (Hsi-Ling-Shih, Lei-Tzu). Silks were originally reserved for

1178-479: Is the second largest producer of silk in the world after China. About 97% of the raw mulberry silk comes from six Indian states, namely, Andhra Pradesh , Karnataka , Jammu and Kashmir , Tamil Nadu , Bihar , and West Bengal . North Bangalore, the upcoming site of a $ 20 million "Silk City" Ramanagara and Mysore , contribute to a majority of silk production in Karnataka. In Tamil Nadu , mulberry cultivation

1240-634: The Great Palace complex in Constantinople, and the cloth produced was used in imperial robes or in diplomacy, as gifts to foreign dignitaries. The remainder was sold at very high prices. Italy was the most important producer of silk during the Medieval age. The first center to introduce silk production to Italy was the city of Catanzaro during the 11th century in the region of Calabria . The silk of Catanzaro supplied almost all of Europe and

1302-730: The Torah , a scarlet cloth item called in Hebrew "sheni tola'at" שני תולעת – literally "crimson of the worm" – is described as being used in purification ceremonies, such as those following a leprosy outbreak (Leviticus 14), alongside cedar wood and hyssop ( za'atar ). Eminent scholar and leading medieval translator of Jewish sources and books of the Bible into Arabic , Rabbi Saadia Gaon , translates this phrase explicitly as "crimson silk" – חריר קרמז حرير قرمز. In Islamic teachings, Muslim men are forbidden to wear silk. Many religious jurists believe

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1364-521: The Yayoi period . The silk industry was dominant from the 1930s to 1950s, but is less common now. Silk from East Asia had declined in importance after silkworms were smuggled from China to the Byzantine Empire. However, in 1845, an epidemic of flacherie among European silkworms devastated the silk industry there. This led to a demand for silk from China and Japan , where as late as

1426-476: The 12th century. Other Italian cities involved in silk production were Genoa , Venice , and Florence . The Piedmont area of Northern Italy became a major silk producing area when water-powered silk throwing machines were developed. The Silk Exchange in Valencia from the 15th century—where previously in 1348 also perxal ( percale ) was traded as some kind of silk—illustrates the power and wealth of one of

1488-595: The 17th century. James I attempted to establish silk production in England, purchasing and planting 100,000 mulberry trees, some on land adjacent to Hampton Court Palace , but they were of a species unsuited to the silk worms, and the attempt failed. In 1732 John Guardivaglio set up a silk throwing enterprise at Logwood mill in Stockport ; in 1744, Burton Mill was erected in Macclesfield ; and in 1753 Old Mill

1550-646: The American silk industry and its counterparts in Japan, and expanded their business to the point that by 1911, the Skinner Mill complex contained the largest silk mill under one roof in the world, and the brand Skinner Fabrics had become the largest manufacturer of silk satins internationally. Other efforts later in the 19th century would also bring the new silk industry to Paterson, New Jersey , with several firms hiring European-born textile workers and granting it

1612-591: The Chinese monopoly . Nonetheless, sericulture reached Korea with technological aid from China around 200 BC, the ancient Kingdom of Khotan by AD 50, and India by AD 140. In the ancient era, silk from China was the most lucrative and sought-after luxury item traded across the Eurasian continent, and many civilizations, such as the ancient Persians, benefited economically from trade. Archaeological evidence indicates that sericulture has been practiced since

1674-567: The Chinese word "sī" and other Asian sources—compare Mandarin sī "silk", Manchurian sirghe , Mongolian sirkek . The production of silk originated in China in the Neolithic period, although it would eventually reach other places of the world ( Yangshao culture, 4th millennium BC). Silk production remained confined to China until the Silk Road opened at some point during

1736-649: The Han period are lost. The first evidence of the long distance silk trade is the finding of silk in the hair of an Egyptian mummy of the 21st dynasty, c.1070 BC. The silk trade reached as far as the Indian subcontinent , the Middle East , Europe , and North Africa . This trade was so extensive that the major set of trade routes between Europe and Asia came to be known as the Silk Road . The emperors of China strove to keep knowledge of sericulture secret to maintain

1798-634: The Japanese silk industry and its position as the lead silk exporter of the world. Today, China exports the largest volume of raw silk in the world. Silk has a long history in India. It is known as Resham in eastern and north India, and Pattu in southern parts of India . Recent archaeological discoveries in Harappa and Chanhu-daro suggest that sericulture , employing wild silk threads from native silkworm species, existed in South Asia during

1860-530: The Middle East by Peter Gaddum . Wild silk taken from the nests of native caterpillars was used by the Aztecs to make containers and as paper. Silkworms were introduced to Oaxaca from Spain in the 1530s and the region profited from silk production until the early 17th century, when the king of Spain banned export to protect Spain's silk industry. Silk production for local consumption has continued until

1922-655: The Polymer Research Institute at Brooklyn Polytechnic , the first research facility in the United States dedicated to polymer research. Mark is also recognized as a pioneer in establishing curriculum and pedagogy for the field of polymer science. In 1950, the POLY division of the American Chemical Society was formed, and has since grown to the second-largest division in this association with nearly 8,000 members. Fred W. Billmeyer, Jr.,

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1984-486: The cultivated silkworm. A technique known as demineralizing allows the mineral layer around the cocoon of wild silk moths to be removed, leaving only variability in color as a barrier to creating a commercial silk industry based on wild silks in the parts of the world where wild silk moths thrive, such as in Africa and South America. Silk use in fabric was first developed in ancient China. The earliest evidence for silk

2046-747: The development of methods for identification and structure analyses of biological macromolecules . 2000 (Chemistry) Alan G. MacDiarmid , Alan J. Heeger , and Hideki Shirakawa for work on conductive polymers , contributing to the advent of molecular electronics . 1991 (Physics) Pierre-Gilles de Gennes for developing a generalized theory of phase transitions with particular applications to describing ordering and phase transitions in polymers. 1974 (Chemistry) Paul J. Flory for contributions to theoretical polymer chemistry. 1963 (Chemistry) Giulio Natta and Karl Ziegler for contributions in polymer synthesis. ( Ziegler-Natta catalysis ). 1953 (Chemistry) Hermann Staudinger for contributions to

2108-511: The domesticated varieties in colour and texture and are therefore less uniform; second, cocoons gathered in the wild have usually had the pupa emerge from them before being discovered so the silk thread that makes up the cocoon has been torn into shorter lengths; and third, many wild cocoons are covered in a mineral layer that prevents attempts to reel from them long strands of silk. Thus, the only way to obtain silk suitable for spinning into textiles in areas where commercial silks are not cultivated

2170-677: The early center of the silk industry in America, when the Cheney Brothers became the first in the United States to properly raise silkworms on an industrial scale; today the Cheney Brothers Historic District showcases their former mills. With the mulberry tree craze of that decade, other smaller producers began raising silkworms. This economy particularly gained traction in the vicinity of Northampton, Massachusetts and its neighboring Williamsburg , where

2232-411: The emperors of China for their own use and gifts to others, but spread gradually through Chinese culture and trade both geographically and socially, and then to many regions of Asia . Because of its texture and lustre, silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants. Silk was in great demand, and became a staple of pre- industrial international trade . Silk

2294-441: The first commercially successful product of polymer research. In 1884 Hilaire de Chardonnet started the first artificial fiber plant based on regenerated cellulose , or viscose rayon , as a substitute for silk , but it was very flammable. In 1907 Leo Baekeland invented the first synthetic plastic, a thermosetting phenol – formaldehyde resin called Bakelite . Despite significant advances in polymer synthesis,

2356-500: The golden silk, and Eri are produced by silkworms that are native only to Assam. They have been reared since ancient times similar to other East and South-East Asian countries. Silk is produced year-round in Thailand by two types of silkworms, the cultured Bombycidae and wild Saturniidae. Most production is after the rice harvest in the southern and northeastern parts of the country. Women traditionally weave silk on hand looms and pass

2418-571: The great Mediterranean mercantile cities. Silk was produced in and exported from the province of Granada , Spain, especially the Alpujarras region, until the Moriscos , whose industry it was, were expelled from Granada in 1571. Since the 15th century, silk production in France has been centered around the city of Lyon where many mechanic tools for mass production were first introduced in

2480-410: The increased production of synthetic substitutes, such as nylon and synthetic rubber . In the intervening years, the development of advanced polymers such as Kevlar and Teflon have continued to fuel a strong and growing polymer industry. The growth in industrial applications was mirrored by the establishment of strong academic programs and research institutes. In 1946, Herman Mark established

2542-557: The largest silk exporter in the world. This increase in exports was mostly due to the economic reforms during the Meiji period and the decline of the Qing dynasty in China, which led to rapid industrialization of Japan whilst the Chinese industries stagnated. During World War II , embargoes against Japan had led to adoption of synthetic materials such as nylon , which led to the decline of

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2604-460: The latter part of the 1st millennium BC, though China maintained its virtual monopoly over silk production for another thousand years. Several kinds of wild silk, produced by caterpillars other than the mulberry silkworm, have been known and spun in China , South Asia , and Europe since ancient times. However, the scale of production was always far smaller than for cultivated silks. There are several reasons for this: first, they differ from

2666-467: The lustrous quality of silk fabric. Aristotle wrote of Coa vestis , a wild silk textile from Kos . Sea silk from certain large sea shells was also valued. The Roman Empire knew of and traded in silk, and Chinese silk was the most highly priced luxury good imported by them. During the reign of emperor Tiberius , sumptuary laws were passed that forbade men from wearing silk garments, but these proved ineffectual. The Historia Augusta mentions that

2728-558: The material from becoming sticky. In 1844 Charles Goodyear received a U.S. patent for vulcanizing natural rubber with sulfur and heat. Thomas Hancock had received a patent for the same process in the UK the year before. This process strengthened natural rubber and prevented it from melting with heat without losing flexibility. This made practical products such as waterproofed articles possible. It also facilitated practical manufacture of such rubberized materials. Vulcanized rubber represents

2790-443: The molecular nature of polymers was not understood until the work of Hermann Staudinger in 1922. Prior to Staudinger's work, polymers were understood in terms of the association theory or aggregate theory, which originated with Thomas Graham in 1861. Graham proposed that cellulose and other polymers were colloids , aggregates of molecules having small molecular mass connected by an unknown intermolecular force. Hermann Staudinger

2852-437: The natural polymer cellulose , producing new, semi-synthetic materials, such as celluloid and cellulose acetate . The term "polymer" was coined in 1833 by Jöns Jakob Berzelius , though Berzelius did little that would be considered polymer science in the modern sense. In the 1840s, Friedrich Ludersdorf and Nathaniel Hayward independently discovered that adding sulfur to raw natural rubber ( polyisoprene ) helped prevent

2914-488: The nickname "Silk City" as another major center of production in the United States. World War II interrupted the silk trade from Asia, and silk prices increased dramatically. U.S. industry began to look for substitutes, which led to the use of synthetics such as nylon . Synthetic silks have also been made from lyocell , a type of cellulose fiber, and are often difficult to distinguish from real silk (see spider silk for more on synthetic silks). In Terengganu , which

2976-422: The nineteenth and early twentieth centuries, Japanese exports competed directly with Chinese in the international market in such low value-added, labor-intensive products as raw silk. Between 1850 and 1930, raw silk ranked as the leading export for both countries, accounting for 20%–40% of Japan's total exports and 20%–30% of China's. Between the 1890s and the 1930s, Japanese silk exports quadrupled, making Japan

3038-586: The present day, sometimes spinning wild silk. King James I introduced silk-growing to the British colonies in America around 1619, ostensibly to discourage tobacco planting. The Shakers in Kentucky adopted the practice. The history of industrial silk in the United States is largely tied to several smaller urban centers in the Northeast region. Beginning in the 1830s, Manchester, Connecticut emerged as

3100-399: The reasoning behind the prohibition lies in avoiding clothing for men that can be considered feminine or extravagant. There are disputes regarding the amount of silk a fabric can consist of (e.g., whether a small decorative silk piece on a cotton caftan is permissible or not) for it to be lawful for men to wear, but the dominant opinion of most Muslim scholars is that the wearing of silk by men

3162-466: The region: mulberry, endi, and tassar. Bengali silk was a major item of international trade for centuries. It was known as Ganges silk in medieval Europe. Bengal was the leading exporter of silk between the 16th and 19th centuries. The 7th century CE murals of Afrasiyab in Samarkand , Sogdiana , show a Chinese Embassy carrying silk and a string of silkworm cocoons to the local Sogdian ruler. In

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3224-748: The silkworms on mulberry leaves. Once the worms start pupating in their cocoons, these are dissolved in boiling water in order for individual long fibres to be extracted and fed into the spinning reel. To produce 1 kg of silk, 104 kg of mulberry leaves must be eaten by 3000 silkworms. It takes about 5000 silkworms to make a pure silk kimono . The major silk producers are China (54%) and India (14%). Other statistics: Production in Int $ 1000 have been calculated based on 1999–2001 international prices Source: Food And Agricultural Organization of United Nations: Economic And Social Department: The Statistical Division The environmental impact of silk production

3286-400: The skill on to their daughters, as weaving is considered to be a sign of maturity and eligibility for marriage. Thai silk textiles often use complicated patterns in various colours and styles. Most regions of Thailand have their own typical silks. A single thread filament is too thin to use on its own so women combine many threads to produce a thicker, usable fiber. They do this by hand-reeling

3348-569: The third-century emperor Elagabalus was the first Roman to wear garments of pure silk, whereas it had been customary to wear fabrics of silk/cotton or silk/linen blends. Despite the popularity of silk, the secret of silk-making only reached Europe around AD 550, via the Byzantine Empire . Contemporary accounts state that monks working for the emperor Justinian I smuggled silkworm eggs to Constantinople from China inside hollow canes. All top-quality looms and weavers were located inside

3410-435: The threads onto a wooden spindle to produce a uniform strand of raw silk. The process takes around 40 hours to produce a half kilogram of silk. Many local operations use a reeling machine for this task, but some silk threads are still hand-reeled. The difference is that hand-reeled threads produce three grades of silk: two fine grades that are ideal for lightweight fabrics, and a thick grade for heavier material. The silk fabric

3472-727: The time of the Indus Valley civilisation (now in Pakistan and India) dating between 2450 BC and 2000 BC. Shelagh Vainker, a silk expert at the Ashmolean Museum in Oxford, who sees evidence for silk production in China "significantly earlier" than 2500–2000 BC, suggests, "people of the Indus civilization either harvested silkworm cocoons or traded with people who did, and that they knew a considerable amount about silk." India

3534-457: The understanding of macromolecular chemistry. Silk Silk is a natural protein fiber , some forms of which can be woven into textiles . The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons . The best-known silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity ( sericulture ). The shimmering appearance of silk

3596-685: Was also used as a surface for writing, especially during the Warring States period (475–221 BCE). The fabric was light, it survived the damp climate of the Yangtze region, absorbed ink well, and provided a white background for the text. In July 2007, archaeologists discovered intricately woven and dyed silk textiles in a tomb in Jiangxi province, dated to the Eastern Zhou dynasty roughly 2,500 years ago. Although historians have suspected

3658-830: Was built in Congleton . These three towns remained the centre of the English silk throwing industry until silk throwing was replaced by silk waste spinning . British enterprise also established silk filature in Cyprus in 1928. In England in the mid-20th century, raw silk was produced at Lullingstone Castle in Kent. Silkworms were raised and reeled under the direction of Zoe Lady Hart Dyke , later moving to Ayot St Lawrence in Hertfordshire in 1956. During World War II , supplies of silk for UK parachute manufacture were secured from

3720-470: Was by tedious and labor-intensive carding . Some natural silk structures have been used without being unwound or spun. Spider webs were used as a wound dressing in ancient Greece and Rome, and as a base for painting from the 16th century. Caterpillar nests were pasted together to make a fabric in the Aztec Empire . Commercial silks originate from reared silkworm pupae, which are bred to produce

3782-619: Was sold in a large market fair in the port of Reggio Calabria , to Spanish, Venetian, Genovese, and Dutch merchants. Catanzaro became the lace capital of the world with a large silkworm breeding facility that produced all the laces and linens used in the Vatican. The city was world-famous for its fine fabrication of silks, velvets, damasks, and brocades. Another notable center was the Italian city-state of Lucca which largely financed itself through silk-production and silk-trading, beginning in

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3844-502: Was the first to propose that polymers consisted of long chains of atoms held together by covalent bonds . It took over a decade for Staudinger's work to gain wide acceptance in the scientific community, work for which he was awarded the Nobel Prize in 1953. The World War II era marked the emergence of a strong commercial polymer industry. The limited or restricted supply of natural materials such as silk and rubber necessitated

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