unit1
1.Not all polymers are built up from bonding together a single kind of repeating unit. At the other extreme ,protein molecules are polyamides in which n amino acide repeat units are bonded together. Although we might still call n the degree of polymerization in this ca, it is less ufull,since an amino acid unit might be any one of some 20-odd molecules that are found in proteins. In this ca the molecular weight itlf,rather than the degree of the polymerization ,is generally ud to describe the molecule. When the actual content of individual amino acids is known,it is their quence that is of special interest to biochemists and molecular biologists.并不是所有的聚合物都是由一个重复单元链接在一起而形成的。在另一个极端的情形中,蛋白质分子是由n个氨基酸重复单元链接在一起形成的聚酰胺。尽管在这个例子中,我们也许仍然把n称为聚合度,但是没有意义,因为一个氨基酸单元也许是在蛋白质中找到的20多个分子中的任意一个。在这种情况下,一般是分子量本身而不是聚合度被用来描述这个分子。当知道了特定的氨基酸分子的实际含量,它们的序列正是生物化学家和分子生物学家特别感兴趣的地方。
1,题目:Another striking ...答案:.that quantity low saturation bottom much absorb
2. 乙烯分子带有一个双键,为一种烯烃,它可以通过连锁聚合大量地制造聚乙烯,目前,聚乙烯已经广泛应用于许多技术领域和人们的日常生活中,成为一种不可缺少的材料。
Ethylene molecule with a double bond, as a kind of olefins, it can make chain polymerization polyethylene, at prent, polyethylene has been widely ud in many fields of technology and People's Daily life, become a kind of indispensable materials.
Unit3
1 The polymerization rate may be experimentally followed by measuring the changes in any of veral properties of the system such as density,refractive index,viscosity, or light absorption. Density measurements are among the most accurate and nsitive of the techniques. The density increas by 20-25 percent on polymerization for many monomers. In actual practice the volume of the polymerizing system is measured by carrying out the reaction in a dilatometer. This is specially constructed vesl with a capillary tube which allows a highly accurate measurement of small volume changes. It is not uncommon to be able to detect a few hundredths of a percent polymerization by the d
ilatometer technique. 聚合速率在实验上可以通过测定体系的任一性质的变化而确定,如密度、折射率、黏度、或者吸光性能。密度的测量是这些技术中最准确最敏感的。对许多单体的聚合来说,密度增加了20%-25%。在实际操作中,聚合体系的体积是通过在膨胀计中进行反应测定的。它被专门设计构造了毛细导管,在里面可以对微小体积变化进行高精确度测量。通过膨胀计技术探测聚合过程中万分之几的变化是很常见的。
Unti4
2 合成聚合物在各个领域中起着与日俱增的重要作用,聚合物通常是由单体通过加成聚合与缩合聚合制成的。就世界上的消耗量而论,聚烯烃和乙烯基聚合物居领先地位,聚乙烯、聚丙烯等属聚烯烃,而聚氯乙烯、聚苯乙烯等则为乙烯基聚合物。聚合物可广泛地用作塑料、橡胶、纤维、涂料、粘合剂等The synthetic polymers play an increasingly important role on a range of domains, which are synthesized by monomers through addition polymerization or condensation polymerization. Polyolefin and vinyl polymer have taken the lead in terms of the world consumption. PE, PP, etc. belong to the polyolefin, while PS, PVC etc. belong to the vinyl polymer. Polymers can be widely applied in plastics, rubbers, fibers, coatings, glues and so on.
基础底板
Unit7
Ring-opening polymerizations proceed only by ionic mechanisms, the polymerization of cyclic ethers mainly by cationic mechanisms, and the polymerization of lactones and lactones by either a cationic or anionic mechanism. Important initiators for cyclic ethers and lactone polymerization are tho derived from aluminum alkyl and zinc alkyl/water systems. It should be pointed out that substitution near the reactive group of the monomer is esntial for the individual mechanism that operates effectively in specific cas; for example, epoxides polymerize readily with cationic and anionic initiators, while fluorocarbon epoxides polymerize exclusively by anionic mechanisms.开环聚合反应只能通过离子机理进行,环醚(的开环)聚合主要通过阳离子机理,而内酯和内酰胺的聚合物是通过阳离子或阴离子机理。对于环醚和内酯型聚合物很重要的引发剂是那些来自于烷基铝和烷基锌/水的体系。应该指出的是(对于)在活性基团附近有取代的单体,只能由单一机理,(这一机理)是在特定条件下的有效操作,例如环氧聚合能用阳离子和阴离子引发剂,然而碳氟环氧化物的聚合只能是阴离子机理。
Chine | English | Molecular Structure |
聚丁二烯 | polybutadiene | |
聚苯乙烯 | Polystyrene | |
三氯化钛 | titanium trichloride | |
四氢呋喃 | Tetrahydrofuran | |
丁基锂 | 胎教音乐100首必听 butyl lithium | CH3雪域魅影木薯可以吃吗CH2CH2CH2—Li |
早孕b超看性别异丁烯 | isobutylene | |
酚钠 | Phenol sodium | |
氯化钠 | sodium chloride | 律师收费管理办法 NaCl |
烯丙基 | Allyl | CH2=CH—CH2— |
光气,碳酰氯 | phosgene | |
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Unti8
1 Polymers can be classified into two main groups, addition polymers and ___condensation__ polymers. This classification is bad on whether or not the repeating unit of the polymer contains the same atoms __as____ the monomer. The repeating unit of an addition polymer is identical _with/to____ the monomer, while condensation polymers contain __different/less___ becau of formation of __compound/byproduct___ during the polymerization process. The corresponding polymerization procesd would then be called addition polymerization and condensation polymerization. As was mentioned earlier, this classification can result ___in__ confusion, since it has been shown in later years that many important types of polymers can be _prepared by both addition and condensation process. For example, polyesters, polyamides and polyurethanes are usually considered to be _condensation____ polymers, but they can be prepared by addition as well as by condensation reaction. Similarly, polyethylene normally considered an _addition_ polymer, can also be prepared by _condensation_ reaction.
2. Answer the following questions in English
(1) What is chain polymerization?
Many olefinic and vinyl unsaturated compounds are able to form chain-like macromolecules through elimination of double bond.
(2) Which kinds of monomers can carry out step-growth polymerization process?
There are two kinds of monomers could carry out step-growth polymerization process. One is polyfunctional monomers and the other is a single monomer containing both types of functional groups.
(3) What properties of polymers can be bad on for measuring the molecular weight?
The molecular weight of polymer could be measured bad on colligative properties, light scattering, viscosity, ultracentrifugation dimentation.
3. Plea write out at least 10 kinds of polymers both in English and in Chine
Polyester聚酯 | polystyrene,聚苯乙烯 | polyamide聚酰胺 | polypropylene聚丙稀 |
polyethylene聚乙烯 | polyurethane聚氨酯 | polyvinyl alcohol 聚乙烯醇 | Polyvinylchloride 聚氯乙烯 |
嘉庆之死polybutene聚丁烯 | polyether聚醚 | | |
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关于安全的作文
4. Plea write out at least 10 kinds of monomers both in English and in Chine and the corresponging chemical structure