高分子材料专业英语第二版部分答案2.pdf

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1、unit1 all polymers are built up from bonding together a single kind of repeating unit.At the otherextreme,protein molecules are polyamides in which n amino acide repeat units are bondedtogether.Although we might still call n the degree of polymerization in this case,it isless usefull,since an amino

2、acid unit might be any one of some 20-odd molecules that are foundin proteins.In this case the molecular weight itself,rather than the degree of thepolymerization,is generally used to describe the molecule.When the actual content ofindividual amino acids is known,it is their sequence that is of spec

3、ial interest to biochemistsand 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 quanti

4、ty low saturation bottom much absorb2.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 polymerizationpolyethylene,at present,polyethylene has been widely used in many fields of technology andPeople

5、s Daily life,become a kind of indispensable materials.Unit31 The polymerization rate may be experimentally followed by measuring the changes in anyof several properties of the system such as density,refractive index,viscosity,or lightabsorption.Density measurements are among the most accurate and se

6、nsitive of the techniques.The density increases by 20-25 percent on polymerization for many monomers.In actual practicethe volume of the polymerizing system is measured by carrying out the reaction in a dilatometer.This is specially constructed vessel with a capillary tube which allows a highly accu

7、ratemeasurement of small volume changes.It is not uncommon to be able to detect a few hundredthsof a percent polymerization by the dilatometer 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

8、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。Unti42 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,whichare synthesized by monomers through add

9、ition 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 canbe widely applied in plastics,rubbers,fibers,coatings,glues and so on.Uni

10、t7Ring-opening polymerizations proceed only by ionic mechanisms,the polymerization of cyclicethers mainly by cationic mechanisms,and the polymerization of lactones and lactones byeither a cationic or anionic mechanism.Important initiators for cyclic ethers and lactonepolymerization are those derived

11、 from aluminum alkyl and zinc alkyl/water systems.It shouldbe pointed out that substitution near the reactive group of the monomer is essential for theindividual mechanism that operates effectively in specific cases;for example,epoxidespolymerize readily with cationic and anionic initiators,while fl

12、uorocarbon epoxidespolymerize 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。Chinese聚丁二烯EnglishpolybutadieneMolecular Structur

13、eCH2CHCHCH2nCH2CHn聚苯乙烯Polystyrenetitanium三氯化钛trichlorideH2CH2CClTiClOClCH2CH2四氢呋喃丁基锂异丁烯酚钠氯化钠烯丙基光气,碳酰氯Unti8Tetrahydrofuranbutyl lithiumisobutylenePhenol sodiumsodium chlorideAllylphosgeneCH3CH2CH2CH2LiH3CCCH3CH2ONaNaClCH2=CHCH2OClCCl1 Polymers can be classified into two main groups,addition polymers

14、and _condensation_polymers.This classification is based on whether or not the repeating unit of the polymercontains the same atoms _as_ the monomer.The repeating unit of an addition polymer isidentical _with/to_ the monomer,while condensation polymers contain _different/less_because of formation of

15、_compound/byproduct_ during the polymerization process.Thecorresponding polymerization processed would then be called addition polymerization andcondensation polymerization.As was mentioned earlier,this classification can result _in_confusion,since it has been shown in later years that many importan

16、t types of polymers canbe _prepared by both addition and condensation processes.For example,polyesters,polyamidesand polyurethanes are usually considered to be _condensation_ polymers,but they can beprepared by addition as well as by condensation reaction.Similarly,polyethylene normallyconsidered an

17、 _addition_ polymer,can also be prepared by _condensation_ reaction.2.Answer the following questions in English(1)What is chain polymerizationManyolefinicandvinylunsaturatedcompoundsareabletoformchain-likemacromoleculesthrougheliminationofdoublebond.(2)Which kinds of monomers can carry out step-grow

18、th polymerization processThere are two kinds of monomers could carry out step-growth polymerization process.Oneispolyfunctionalmonomersandtheotherisasinglemonomercontainingbothtypesoffunctional groups.(3)What properties of polymers can be based on for measuring the molecular weightThe molecular weig

19、ht of polymer could be measured based on colligativeproperties,lightscattering,viscosity,ultracentrifugation sedimentation.3.Please write out at least 10 kinds of polymers both in English and in ChinesePolyester 聚酯polystyrene,聚苯乙烯polyethylene 聚乙烯polyurethane 聚氨酯polyvinyl alcohol聚乙烯醇polybutene 聚丁烯pol

20、yether 聚醚polyamide 聚酰胺polypropylene 聚丙稀Polyvinylchloride聚氯乙烯4.Please write out at least 10 kinds of monomers both in English and in Chinese and thecorresponging chemical structureClCN乙 烯氯 乙 烯丙 烯 1-丁 烯丙 烯 腈ethylene vinylchloride propylene 1-butene acrylonitrileFFCOOHFF1,4-丁 二 烯四 氟 乙 烯苯 乙 烯异 丁 烯丙 烯 酸1

21、,4-butadiene tetrafluoroethylene styrene isobutene acrylic acid5 In general,head-to-tail addition is considered to be the predominant mode of propagationin all polymerizations。However,when the substitutes on the monomer are small(and do notoffer appreciable steric hindrance to the approaching radica

22、l)or do not have a large resonancestabilizing effect,as in the case of fluorine atoms,sizable amounts of head-to-headpropagation may occur.The effect of increasing polymerization temperature is to increasethe amount of head-to-head placement。Increased temperature leads to less selective(morerandom)p

23、ropagation but the effect is not large.Thus,the head-to-head content in poly (vinylacetate)only increasesfrom to percent when the polymerization temperature in increasedfrom 30 to 90.通常在所有聚合物的链增长中,头-尾加成是主要方式。然而,当单体中的取代基很小(对接近的自由基没有空间阻碍)或没有较大的共振稳定作用,如氟原子,则有相当量的头头增长发生。提高聚合温度的影响是提高头-头排列的量。温度的提高导致较少的选择(

24、更多的无规)增长,但影响不大。因而,在聚乙酸乙烯酯中,当聚合温度由30C 提高到 90C,头-头含量仅由%提高到%。2Write out an abstract in English for the text in this unitPolymers with different structures present various properties.Usually,polymers are dividedinto three categories,.plastic,elastomer,fiber with different initial modulus rangerespective

25、ly.Polymers show quite different behaviors due to the different interchain forcesin elastomer and fiber.However,with the advent of new techniques and mechanisms to improvethe structure ofpolymers,polymers may be classified and named according to the mechanism,and their properties will largely depend

26、 on the structure.3Put the following words into Chinese entanglement 纠缠 irregularity 无规 sodium isopropylate异丙醇钠 permeability渗透性crystallite 微晶stoichiomertric balance 当量平衡fractionation 分馏法lightscattering 光散射 matrix 基体 diffraction 衍射 4Put the following words into English形态 morphology酯化 esterification 异

27、氰酸酯 isocyanate杂质 impurity二元胺 diamine 转化率 change ratio多分散性 polydispersity力学性能mechanical property构象 conformation红外光谱法 infrared spectroscopy常见聚合物命名(1)常见杂链和元素有机聚合物类型Polyamide-聚酰胺.Polyester-聚酯 Poly urethane-聚氨酯 Polysiloxane-聚 硅 氧 烷Phenol-formaldehyde-酚 醛.Urea-formaldehyde-脲 醛Polyureas-聚脲Polysulfide-聚硫 Polyacetal-聚缩醛Polysulfone(polysulphone)-聚砜 Polyether-聚醚

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