英文文獻翻譯

1、 外文文獻原稿和譯文原 稿Sodium Polyacrylate:Also known as super- absorbent or “SAP”(super absorbent polymer), Kimberly Clarkused to call it SAM (super absorbent material). It is typically used in fine granular form(like table salt). It helps improve capacity for better retention in a disposable diaper,allowing

2、 the product to be thinner with improved performance and less usage of pine fluffpulp. The molecular structure of the polyacrylate has sodium carboxylate groups hangingoff the main chain. When it comes in contact with water, the sodium detaches itself, leavingonly carboxylions. Being negatively char

3、ged, these ions repel one another so that thepolymer also has cross-links, which effectively leads to a three-dimensional structure. It hashige molecular weight of more than a million; thus, instead of getting dissolved, it solidifiesinto a gel. The Hydrogen in the water (H-O-H) is trapped by the ac

4、rylate due to the atomicbonds associated with the polarity forces between the atoms. Electrolytes in the liquid, suchas salt minerals (urine contains 0.9% of minerals), reduce polarity, thereby affectingsuperabsorbent properties, especially with regard to the superabsorbent capacity for liquidretent

5、ion. This is the main reason why diapers containing SAP should never be tested withplain water. Linear molecular configurations have less total capacity than non-linearmolecules but, on the other hand, retention of liquid in a linear molecule is higher than in anon-linear molecule, due to improved p

6、olarity. For a list of SAP suppliers, please use thislink: SAP, the superabsorbent can be designed to absorb higher amounts of liquids (withless retention) or very high retentions (but lower capacity). In addition, a surface crosslinker can be added to the superabsorbent particle to help it move liq

7、uids while it issaturated. This helps avoid formation of gel blocks, the phenomenon that describes theimpossibility of moving liquids once a SAP particle gets saturated.History of Super Absorbent Polymer Chemistry Until the 1980s, water absorbing materials were cellulosic or fiber-basedproducts. Cho

8、ices were tissue paper, cotton, sponge, and fluff pulp. The water retentioncapacity of these types of materials is only 20 times their weight at most.In the early 1960s, the United States Department of Agriculture (USDA) wasconducting work on materials to improve water conservation in soils. They de

9、veloped aresin based on the grafting of acrylonitrile polymer onto the backbone of starch molecules(i.e. starch-grafting). The hydrolyzed product of the hydrolysis of this starch-acrylonitrileco-polymer gave water absorption greater than 400 times its weight. Also, the gel did notrelease liquid wate

10、r the way that fiber-based absorbents do.The polymer came to be known as “Super Slurper”. The USDA gave the technicalknow how several USA companies for further development of the basic technology. Awide range of grating combinations were attempted including work with acrylic acid,acrylamide and poly

11、vinyl alcohol (PVA).Since Japanese companies were excluded by the USDA, they started independentresearch using starch, carboxy methyl cellulose (CMC), acrylic acid, polyvinyl alcohol(PVA) and isobutylene maleic anhydride (IMA).Early global participants in the development of super absorbent chemistry

12、 includedDow Chemical, Hercules, General Mills Chemical, DuPont, National Starch & Chemical,Enka (Akzo), Sanyo Chemical, Sumitomo Chemical, Kao, Nihon Starch and Japan Exlan.In the early 1970s, super absorbent polymer was used commercially for the first time not for soil amendment applications as or

13、iginally intended but for disposable hygienicproducts. The first product markets were feminine sanitary napkins and adult incontinenceproducts.In 1978, Park Davis (d.b.a. Professional Medical Products) used super absorbentpolymers in sanitary napkins.Super absorbent polymer was first used in Europe

14、in a baby diaper in 1982 whenSchickendanz and Beghin-Say added the material to the absorbent core. Shortly thereafter,UniCharm introduced super absorbent baby diapers in Japan while Proctor & Gamble andKimberly-Clark in the USA began to use the material. The development of super absorbent technology

15、 and performance has been largely ledby demands in the disposable hygiene segment. Strides in absorption performance haveallowed the development of the ultra-thin baby diaper which uses a fraction of the materials particularly fluff pulp which earlier disposable diapers consumed.Over the years, tech

16、nology has progressed so that there is little if any starch-graftedsuper absorbent polymer used in disposable hygienic products. These super absorbentstypically are cross-linked acrylic homo-polymers (usually Sodium neutralized).Super absorbents used in soil amendments applications tend to be cross-

17、linkedacrylic-acrylamide co-polymers (usually Potassium neutralized).Besides granular super absorbent polymers, ARCO Chemical developed a superabsorbent fiber technology in the early 1990s. This technology was eventually sold toCamelot Absorbents. There are super absorbent fibers commercially availa

18、bletoday. While significantly more expensive than the granular polymers, the super absorbentfibers offer technical advantages in certain niche markets including cable wrap, medicaldevices and food packaging.Sodium polyacrylate, also known as waterlock, is a polymer with the chemicalformula -CH -CH(C

19、OONa)- widely used in consumer products. It has the ability to2nabsorb as much as 200 to 300 times its mass in water. Acrylate polymers generally areconsidered to possess an anionic charge. While sodium neutralized polyacrylates are themost common form used in industry, there are also other salts av

20、ailable includingpotassium, lithium and ammonium.ApplicationsAcrylates and acrylic chemistry have a wide variety of industrial uses that include:Sequestering agents in detergents. (By binding hard water elements such as calciumand magnesium, the surfactants in detergents work more efficiently.)Thick

21、ening agentsCoatingsFake snowSuper absorbent polymers. These cross-linked acrylic polymers are referred to asSuper Absorbents and Water Crystals, and are used in baby diapers. Copolymer versions are used in agriculture and other specialty absorbent applications. The origins ofsuper absorbent polymer

22、 chemistry trace back to the early 1960s when the U.S. Departmentof Agriculture developed the first super absorbent polymer materials. This chemical isfeatured in the Maximum Absorbency Garment used by NASA. 譯 文聚丙烯酸鈉聚丙烯酸鈉，又可以稱為超級吸收劑或者又叫高吸水性樹脂，凱博利克拉克教授曾經(jīng)稱它為 SAM 即：超級吸收性物質(zhì)。它經(jīng)常以細小顆粒的形式被應(yīng)用，例如食鹽。它有助于提高一次性

23、尿布的保水能力，提高該產(chǎn)品的使用性能，并且使該產(chǎn)品越做越薄。在聚丙烯酸鈉分子中，羧基連接在主鏈上。當聚丙烯酸鈉分子與水接觸時，分子中鈉分離出去，只剩下羧基。由于分子變成了帶有負電荷的結(jié)構(gòu)，所以這些離子相互排斥，使聚合物分子交叉連接從而有效地形成了三維結(jié)構(gòu)。由于這種結(jié)構(gòu)的分子量超過一百萬，所以它并沒有溶解，而是凝固成凝膠。在水分子H-O-H 中，氫原子穩(wěn)定地存在于丙烯酸中是因為存在原子鍵，這些鍵與分子中的極性鍵密切相關(guān)。在液體中的電解質(zhì)，例如礦物質(zhì)鹽（尿液中的含量為 0.9%）,降低電解質(zhì)的極性，進而會影響吸水性，特別是對于保留高吸水性樹脂的液體容量。這就是為什么含有高吸水性樹脂的尿布不能僅僅用

24、水進行試驗。線性分子的這種構(gòu)造在總吸水量上不如非線性分子，但是另一方面，線性分子的保水性能卻比非線性分子好很多，原因是極性增加提高了保水性能。超級吸收劑可以這樣進行設(shè)計：它可以具有很高的吸水性但是保水性不佳，或者正相反。此外，我們可以在超級保水劑中添加表面交聯(lián)劑，這是一種可以幫助水分子進行移動的添加劑。這樣就可以避免形成凝膠塊的形成，解決了這樣一種難題：SAP分子一旦達到飽和狀態(tài)，它將不再可以被移動。SAP 化學的歷史直到上個世紀八十年代，吸水類物質(zhì)是纖維素或纖維素類的產(chǎn)品。產(chǎn)品僅限于紙巾、棉花、海綿和絨毛漿。這些類型保水類產(chǎn)品的保水能力至多是它們自身質(zhì)量的 20倍。在 60 年代初，美國農(nóng)業(yè)

25、部開始了對吸水材料的研制工作，目的是要提高土壤的保水能力。他們開發(fā)出一種方法，可以在淀粉分子的骨干上把丙烯腈嫁接到上面，即淀粉接枝聚丙烯腈。這種淀粉和丙烯腈的聚合物淀粉接枝聚丙烯腈水解后的吸水能力可以達到 400 倍于自身的質(zhì)量。但是，這種凝膠的釋水能力并沒有纖維素類的凝膠的 釋水能力強。這種聚合物被冠以“超級吸水王”的美名。美國農(nóng)業(yè)部把這項技術(shù)轉(zhuǎn)讓給若干家有能力繼續(xù)深入研究這項基礎(chǔ)技術(shù)的美國公司。他們進行了廣泛的研究，包括把纖維素和各種物質(zhì)進行組合嘗試，產(chǎn)品有纖維素接枝聚丙烯酸，纖維素接枝丙烯酰胺和纖維素聚乙烯醇(PVA)等等。由于日本的公司被美國農(nóng)業(yè)部排斥在外，他們開始獨立進行這方面的研究。他們對淀粉、羧甲基纖維素 (CMC)、丙烯酸、聚乙烯醇 (PVA)和異丁烯、馬來酸酐 (IMA)進行研究。在高效吸水劑化學工業(yè)發(fā)展的早期，很多大的公司參與進來，其中包括陶氏化學、大力士化學、通用米氏化學、杜邦公司，日本國民淀粉化學公司、三洋化學公司、住友化學公司、花王化學公司以及日本淀粉化學公司。在 70 年代初，高吸水性樹脂不僅以前廣泛應(yīng)用于人們的初衷，即改善土壤保水性的領(lǐng)域，而且第一次被應(yīng)用于商業(yè)領(lǐng)域：可任意使用的人們的日常衛(wèi)生用品。但是第一個產(chǎn)品市場是女性衛(wèi)生巾和成人失禁產(chǎn)品。1978 年，帕克戴維斯把高效吸水劑用于衛(wèi)生保水領(lǐng)域。這是一個歷史性的新突破，從此保水劑的應(yīng)用迎來