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1、-第 0 页高分子材料工程专业英语第二版课文翻译(基本全了-第 0 页A高分子化学和高分子物理UNIT 1What are Polymer?第一单元什么是高聚物？What are polymers?For one thing,they are complex and giant molecules and aredifferent from low molecular weight compounds like,say,common salt.To contrastthe difference,the molecular weight of common salt is only 58.5,w
2、hile that ofa polymer can be as high as several hundred thousand,even more than thousandthousands.These big molecules or macro-molecules are made up of much smallermolecules,can be of one or more chemical compounds.To illustrate,imagine thata set of rings has the same size and is made of the same ma
3、terial.When these thingsare interlinked,the chain formed can be considered as representing a polymer frommolecules of the same compound.Alternatively,individual rings could be ofdifferent sizes and materials,and interlinked to represent a polymer frommolecules of different compounds.什么是高聚物？首先，他们是合成物
4、和大分子，而且不同于低分子化合物，譬如说普通的盐。与低分子化合物不同的是，普通盐的分子量仅仅是 58.5，而高聚物的分子量高于 105，甚至大于 106。这些大分子或“高分子”由许多小分子组成。小分子相互结合形成大分子，大分子能够是一种或多种化合物。举例说明，想象一组大小相同并由相同的材料制成的环。当这些环相互连接起来，可以把形成的链看成是具有同种分子量化合物组成的高聚物。另一方面，独特的环可以大小不同、材料不同，相连接后形成具有不同分子量化合物组成的聚合物。This interlinking of many units has given the polymer its name,poly
5、meaning manyand mer meaning part(in Greek).As an example,a gaseous compound calledbutadiene,with a molecular weight of 54,combines nearly 4000 times and givesa polymer known as polybutadiene(a synthetic rubber)with about 200 000molecularweight.The low molecular weight compounds from which the polyme
6、rs form are knownas monomers.The picture is simply as follows:许多单元相连接给予了聚合物一个名称，poly 意味着“多、聚、重复”，mer 意味着“链节、基体”（希腊语中）。例如：称为丁二烯的气态化合物，分子量为 54，化合将近 4000次，得到分子量大约为 200000 被称作聚丁二烯（合成橡胶）的高聚物。形成高聚物的低分子化合物称为单体。下面简单地描述一下形成过程：butadiene+butadiene+butadiene-polybutadiene(4 000 time)丁二烯 丁二烯丁二烯聚丁二烯（4000 次）One ca
7、n thus see how a substance(monomer)with as small a molecule weight as 54grow to become a giant molecule(polymer)of(544 000)200 000 molecular weight.It is essentially the giantness of the size of the polymer molecule that makesits behavior different from that of a commonly known chemical compound suc
8、h as-第 1 页benzene.Solid benzene,for instance,melts to become liquid benzene at 5.5 and,on further heating,boils into gaseous benzene.As against this well-definedbehavior of a simple chemical compound,a polymer like polyethylene does not meltsharply at one particular temperature into clean liquid.Ins
9、tead,it becomesincreasingly softer and,ultimately,turns into a very viscous,tacky molten mass.Further heating of this hot,viscous,molten polymer does convert it into variousgases but it is no longer polyethylene.(Fig.1.1).因而能够看到分子量仅为 54 的小分子物质（单体）如何逐渐形成分子量为 200000 的大分子（高聚物）。实质上，正是由于聚合物的巨大的分子尺寸才使其性能不
10、同于象苯这样的一般化合物。例如，固态苯，在 5.5熔融成液态苯，进一步加热，煮沸成气态苯。与这类简单化合物明确的行为相比，像聚乙烯这样的聚合物不能在某一特定的温度快速地熔融成纯净的液体。而聚合物变得越来越软，最终，变成十分粘稠的聚合物熔融体。将这种热而粘稠的聚合物熔融体进一步加热，不会转变成各种气体，但它不再是聚乙烯（如图 1.1）。固态苯液态苯气态苯加热，5.5加热，80固体聚乙烯熔化的聚乙烯各种分解产物-但不是聚乙烯加热加热图 1.1 低分子量化合物（苯）和聚合物（聚乙烯）受热后的不同行为Another striking difference with respect to the beh
11、avior of a polymer and thatof a low molecular weight compound concerns the dissolution process.Let us take,for example,sodium chloride and add it slowly to s fixed quantity of water.Thesalt,which represents a low molecular weight compound,dissolves in water up tos point(called saturation point)but,t
12、hereafter,any further quantity added doesnot go into solution but settles at the bottom and just remains there as solid.The viscosity of the saturated salt solution is not very much different from thatof water.But if we take a polymer instead,say,polyvinyl alcohol,and add itto a fixed quantity of wa
13、ter,the polymer does not go into solution immediately.The globules of polyvinyl alcohol first absorb water,swell and get distorted inshape and after a long time go into solution.Also,we can add a very large quantityof the polymer to the same quantity of water without the saturation point everbeing r
14、eached.As more and more quantity of polymer is added to water,the timetaken for the dissolution of the polymer obviously increases and the mix ultimatelyassumes a soft,dough-like consistency.Another peculiarity is that,in water,polyvinyl alcohol never retains its original powdery nature as the exces
15、s sodiumchloride does in a saturated salt solution.In conclusion,we can say that(1)the long time taken by polyvinyl alcohol for dissolution,(2)the absence of asaturation point,and(3)the increase in the viscosity are all characteristicsof a typical polymer being dissolved in a solvent and thesecharac
16、teristics areattributed mainly to the large molecular size of the polymer.The behavior of a-第 2 页low molecular weight compound and that of a polymer on dissolution are illustratedin Fig.1.2.发现另一种不同的聚合物行为和低分子量化合物行为是关于溶解过程。例如，让我们研究一下，将氯化钠慢慢地添加到固定量的水中。盐，代表一种低分子量化合物，在水中达到点（叫饱和点）溶解，但，此后，进一步添加盐不进入溶液中却沉到底部
17、而保持原有的固体状态。饱和盐溶液的粘度与水的粘度不是十分不同，但是，如果我们用聚合物替代，譬如说，将聚乙烯醇添加到固定量的水中，聚合物不是马上进入到溶液中。聚乙烯醇颗粒首先吸水溶胀，发生形变，经过很长的时间以后进入到溶液中。同样地，我们可以将大量的聚合物加入到同样量的水中，不存在饱和点。将越来越多的聚合物加入水中，认为聚合物溶解的时间明显地增加，最终呈现柔软像面团一样粘稠的混合物。另一个特点是，在水中聚乙烯醇不会像过量的氯化钠在饱和盐溶液中那样能保持其初始的粉末状态。总之，我们可以讲（1）聚乙烯醇的溶解需要很长时间，（2）不存在饱和点，（3）粘度的增加是典型聚合物溶于溶液中的特性，这些特性主要
18、归因于聚合物大分子的尺寸。如图 1.2 说明了低分子量化合物和聚合物的溶解行为。氯化钠晶体加入到水中晶体进入到溶液中.溶液的粘度不是十分不同于充分搅拌水的粘度形成饱和溶液.剩余的晶体维持不溶解状态.加入更多的晶体并搅拌氯化钠的溶解聚乙烯醇碎片加入到水中碎片开始溶胀碎片慢慢地进入到溶液中允许维持现状充分搅拌形成粘稠的聚合物溶液.溶液粘度十分高于水的粘度继续搅拌聚合物的溶解图 1.2 低分子量化合物（氯化钠）和聚合物（聚乙烯醇）不同的溶解行为Gowariker VR,Viswanathan N V,Sreedhar J.Polymer Science.New York:John Wiley&Son
19、s,1986.6UNIT 2Chain Polymerization第二单元 链式聚合反应Many olefinic and vinyl unsaturated compounds are able to form chain-0likemacromolecules through elimination of the double bond,a phenomenon firstrecognized by Staudinger.Diolefins polymerize in the same manner,however,onlyone of the two double bonds is e
20、liminated.Such reactions occur through the initialaddition of a monomer molecule to an initiator radical or an initiator ion,bywhich the active state is transferred from the initiator to the added monomer.In the same way by means of a chain reaction,one monomer molecule after the otheris added(20002
21、0000 monomers per second)until the active state is terminatedthrough a different type of reaction.The polymerization is a chain reaction intwo ways:because of the reaction kinetic and because as a reaction product one-第 3 页obtains a chain molecule.The length of the chain molecule is proportional to
22、thekinetic chain length.Staudinger 第一个发现一例现象，许多烯烃和不饱和烯烃通过打开双键可以形成链式大分子。二烯烃以同样的方式聚合，然而，仅限于两个双键中的一个。这类反应是通过单体分子首先加成到引发剂自由基或引发剂离子上而进行的，靠这些反应活性中心由引发剂转移到被加成的单体上。以同样的方式，借助于链式反应，单体分子一个接一个地被加成（每秒 200020000 个单体）直到活性中心通过不同的反应类型而终止。聚合反应是链式反应的原因有两种：因为反应动力学和因为作为反应产物它是一种链式分子。链分子的长度与动力学链长成正比。One can summarize the
23、process as follow(R.is equal to the initiator radical):链式反应可以概括为以下过程（R相当与引发剂自由基）：略One thus obtains polyvinylchloride from vinylchloride,or polystyrene from styrene,or polyethylene from ethylene,etc.因而通过上述过程由氯乙烯得到聚氯乙烯，或由苯乙烯获得聚苯乙烯，或乙烯获得聚乙烯，等等。The length of the chain molecules,measured by means of the
24、degree of polymerization,can be varied over a large range through selection of suitable reaction conditions.Usually,withcommerciallypreparedandutilizedpolymers,thedegreeofpolymerization lies in the range of 1000 to 5000,but in many cases it can be below500 and over 10000.This should not be interpret
25、ed to mean that all molecules ofa certain polymeric material consist of 500,or 1000,or 5000 monomer units.Inalmost all cases,the polymeric material consists of a mixture of polymer moleculesof different degrees of polymerization.借助于聚合度估算的分子链长，在一个大范围内可以通过选择适宜的反应条件被改变。通常，通过大量地制备和利用聚合物，聚合度在 10005000 范围
26、内，但在许多情况下可低于 500、高于 10000。这不应该把所有聚合物材料的分子量理解为由 500，或 1000，或 5000个单体单元组成。在几乎所有的事例中，聚合物材料由不同聚合度的聚合物分子的混合物组成。Polymerization,a chain reaction,occurs according to the same mechanism as thewell-known chlorine-hydrogen reaction and the decomposition of phosegene.聚合反应，链式反应，依照与众所周知的氯（气）-氢（气）反应和光气的分解机理进行。The
27、initiation reaction,which is the activation process of the double bond,canbe brought about by heating,irradiation,ultrasonics,or initiators.Theinitiation of the chain reaction can be observed most clearly with radical or ionicinitiators.These are energy-rich compounds which can add suitable unsatura
28、tedcompounds(monomers)and maintain the activated radical,or ionic,state so thatfurther monomer molecules can be added in the same manner.For the individual stepsof the growth reaction one needs only a relatively small activation energy andtherefore through a single activation step(the actual initiat
29、ion reaction)a large-第 4 页number of olefin molecules are converted,as is implied by the term“chainreaction”.Because very small amounts of the initiator bring about the formationof a large amount of polymeric material(1:1000 to 1:1000),it is possible to regardpolymerization from a superficial point o
30、f view as a catalytic reaction.For thisreason,the initiators used in polymerization reactions are often designated aspolymerization catalysts,even though,in the strictest sense,they are not truecatalysts because the polymerization initiator enters into the reaction as a realpartner and can be found
31、chemically bound in the reaction product,i.e.,the polymer,In addition to the ionic and radical initiators there are now metal complexinitiators(which can be obtained,for example,by the reaction of titaniumtetrachloride or titanium trichloride with aluminum alkyls),which play animportant role in poly
32、merization reactions(Ziegler catalysts),The mechanism oftheir catalytic action is not yet completely clear.双键活化过程的引发剂反应，可以通过热、辐射、超声波或引发剂产生。用自由基型或离子型引发剂引发链式反应可以很清楚地进行观察。这些是高能态的化合物，它们能够加成不饱和化合物（单体）并保持自由基或离子活性中心 以致单体可以以同样的方式进一步加成。对于增长反应的各个步骤，每一步仅需要相当少的活化能，因此通过一步简单的活化反应（即引发反应）即可将许多烯类单体分子转化成聚合物，这正如连锁反应这个
33、术语的内涵那样。因为少量的引发剂引发形成大量的聚合物原料（1：10001：10000），从表面上看聚合反应很可能是催化反应。由于这个原因，通常把聚合反应的引发剂看作是聚合反应的引发剂，但是，严格地讲它们不是真正意义上的催化剂，因为聚合反应的催化剂进入到反应内部而成为一部分，同时可以在反应产物，既聚合物的末端发现。此外离子引发剂和自由基引发剂有的是金属络合物引发剂（例如，通过四氯化钛或三氯化钛与烷基铝的反应可以得到），Z 引发剂在聚合反应中起到了重要作用，它们催化活动的机理还不是十分清楚。UNIT 3Step-Growth Polymerization第三单元逐步聚合Many different
34、 chemical reactions may be used to synthesize polymeric materialsby step-growth polymerization.These include esterification,amidation,theformation of urethanes,aromatic substitution,etc.Polymerization proceeds bythe reactions between two different functional groups,e.g.,hydroxyl and carboxylgroups,o
35、r isocyanate and hydroxyl groups.许多不同的化学反应通过逐步聚合可用于合成聚合材料。这些反应包括酯化、酰胺化、氨基甲酸酯、芳香族取代物的形成等。通过反应聚合反应在两种不同的官能团，如，羟基和羧基，或异氰酸酯和羟基之间。All step-growth polymerization fall into two groups depending on the type ofmonomer(s)employed.The first involves two different polyfunctional monomers inwhich each monomer po
36、ssesses only one type of functional group.A polyfunctionalmonomer is one with two or more functional groups per molecule.The second involves-第 5 页a single monomer containing both types of functional groups.The synthesis ofpolyamides illustrates both groups of polymerization reactions.Thus,polyamides
37、can be obtained from the reaction of diamines with diacids所有的逐步聚合反应根据所使用单体的类型可分为两类。第一类涉及两种不同的官能团单体，每一种单体仅具有一种官能团。一种多官能团单体每个分子有两个或多个官能团。第二类涉及含有两类官能团的单种单体。聚酰胺的合成说明了聚合反应的两个官能团。因此聚酰胺可以由二元胺和二元酸的反应或氨基酸之间的反应得到。nH2N-R-NH2+nHO2C-R-CO2HH-(-NH-R-NHCO-R-CO-)n-OH+(2n-1)H2O(3.1)or from the reaction of amino acids
38、 with themselvesnH2R-CO2H H-(-NH-R-CO-)n-OH+(n-1)H20(3.2)The two groups of reactions can be represented in a general manner by the equationsas followsA+B-B-A-A-B-B-A-B-A-B-两种官能团之间的反应一般来说可以通过下列反应式表示反应式略Reaction(3.1)illustrates the former,while(3.2)is of the latter type.反应（3.1）说明前一种形式，而反应（3.2）具有后一种形式。
39、图 3.1逐步聚合的示意图未反应单体；（b）50%已反应；（c）83.3%已反应；(d)100%已反应（虚线表示反应种类）Polyesterification,whether between diol and dibasic acid or intermolecularlybetween hydroxy acid molecules,is an example of a step-growth polymerizationprocess.The esterification reaction occurs anywhere in the monomer matrix wheretwo mono
40、mer molecules collide,and once the ester has formed,it,too,can reactfurther by virtue of its still-reactive hydroxyl or carboxyl groups.The net effectof this is that monomer molecules are consumed rapidly without any large increasein molecular weight.Fig.3.1 illustrates this phenomenon.Assume,for ex
41、ample,that each square in Fig.3.a represents a molecule of hydroxy acid.After theinitial dimmer molecules from(b),half the monomer molecules have been consumedand the average degree of polymerization(DP)of polymeric species is 2.As trimerand more dimer molecules form(c),more than 80%of the monomer m
42、olecules havereacted(d),DP is 4.But each polymer molecule that forms still has reactive endgroups;hence the polymerization reaction will continue in a stepwise fashion,with each esterification of monomers.Thus,molecular weight increases slowly evenat high levels of monomer conversion,and it will con
43、tinue to increase until theviscosity build-up makes it mechanically too difficult to remove water ofesterification or for reactive end groups to find each other.聚酯化，是否在二元酸和二元醇或羟基酸分子间进行，是逐步聚合反应过程的一个例子。酯化反应出现在单体本体中两个单体分子相碰撞的位置，且酯一旦形成，依靠酯上仍有活-第 6 页性的羟基或羧基还可以进一步进行反应。酯化的结果是单体分子很快地被消耗掉，而分子量却没有多少增加。图 3.1 说
44、明了这个现象。例如，假定图 3.1 中的每一个方格代表一个羟基酸分子。（b）中的二聚体分子，消耗二分之一的单体分子聚合物种类的聚合度（DP）是 2。（c）中当三聚体和更多的二聚体形成，大于 80%的单体分子已反应，但 DP 仅仅还是2.5。（d）中当所有的单体反应完，DP 是 4。但形成的每一种聚合物分子还有反应活性的端基；因此，聚合反应将以逐步的方式继续进行，其每一步酯化反应的反应速率和反应机理均与初始单体的酯化作用相同。因此，分子量缓慢增加直至高水平的单体转化率，而且分子量将继续增加直到粘度的增加使其难以除去酯化反应的水或难以找到相互反应的端基。It can also be shown t
45、hat in the A-A+B-B type of polymerization,an exactstoichiometric balance is necessary to achieve high molecular weights.If somemonofunctional impurity is present,its reaction will limit the molecular weightby rendering a chain end inactive.Similarly,high-purity monomers are necessaryin the A-B type
46、of polycondensation and it follows that high-yield reactions arethe only practical ones for polymer formation,since side reactions will upsetthe stoichiometric balance.在 A-A+B-B 的聚合反应中也可以看到，精确的当量平衡是获得高分子量所必需的。假如存在一些但官能团杂质，由于链的端基失活，反应将使分子量减少。同样，在 A-B 类的缩聚反应中高纯度的单体是必要的，而且可以归结高收率的反应仅是形成聚合物的实际反应，因为副反应会破
47、坏当量平衡。-Stevens M P.Polymer Chemistry.London:Addison-Wesley Publishing Company,1975.13UNIT 4Ionic Polymerization第四单元 离子聚合反应Ionic polymerization,similar to radial polymerization,also has the mechanismofachainreaction.Thekineticsofionicpolymerizationare,however,considerably different from that of radic
48、al polymerization.离子聚合反应，与自由基聚合反应相似，也有链反应的机理。但是，离子聚合的动力学明显地不同于自由基聚合反应。(1)The initiation reaction of ionic polymerization needs only a small activationenergy.Therefore,the rate of polymerization depends only slightly on thetemperature.Ionic polymerizations occur in many cases with explosive violencee
49、ven at temperature.below 50(for example,the anionic polymerization of styreneat 70 in tetrahydrofuran,or the cationic polymerization of isobutylene at100 in liquid ethylene).(1)离子聚合的引发反应仅需要很小的活化能。因此，聚合反应的速率仅对温度有较少的依赖性。在许多情况下离子聚合猛烈地发生甚至低于 50（例如，苯乙烯的阴离子聚合反应在-70在四氢呋喃中，或异丁烯的阳离子聚合在-100在液态乙烯中）。(2)With ion
50、ic polymerization there is no compulsory chain termination through-第 7 页recombination,because the growing chains can not react with each other.Chaintermination takes place only through impurities,or through the addition of certaincompounds such as water,alcohols,acids,amines,or oxygen,and in general