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built up:构造P1-1P1-1 A polymer is a large molecule A polymer is a large molecule built upbuilt up from numerous from numerous smaller molecules.These large molecules may be linear,slightly smaller molecules.These large molecules may be linear,slightly branchedbranched,or highly,or highly interconnectedinterconnected.In the latter case the structure.In the latter case the structure develops into a large develops into a large three-dimensional networkthree-dimensional network.BASIC CONCEPTS聚合物是由数目众多的较小分子构造而成的一种大分子。这些大分子可以是线型的、简单的支链型的、或者是高度相互交联的。后者的结构发展成一种三维网状结构。are known as:被称为是 poly(vinyl chloried):PVC P1-2 P1-2 The small molecules used as the basic building blocks for The small molecules used as the basic building blocks for these large molecules are known asthese large molecules are known as monomers monomers.For example the.For example the commercially important material commercially important material poly(vinyl chloried)poly(vinyl chloried)is made is made from the monomer vinyl chloride.The repeat unit in the polymer from the monomer vinyl chloride.The repeat unit in the polymer usually corresponds to the monomer from which the polymer was usually corresponds to the monomer from which the polymer was made.made.repeat unit:重复结构单元 corresponds to:相当于构成大分子中基本单元的小分子被称为单体。例如,具有重要商业用途的聚氯乙烯是由氯乙烯单体制成的。聚合物中的重复结构单元常常相当于制成聚合物的单体。no such monomer as vinyl clcohol:没有乙烯醇这样一种单体P1-2P1-2 There are exceptions to this,though.There are exceptions to this,though.Poly(vinyl alcohol)Poly(vinyl alcohol)is formally considered to be made up of vinyl alcohol is formally considered to be made up of vinyl alcohol(CH2CHOH)repeat units but there is,in fact,(CH2CHOH)repeat units but there is,in fact,no such monomer no such monomer as vinyl clcoholas vinyl clcohol.虽然也有例外。聚乙烯醇一般会被认为是由乙烯醇这种重复单元制成的,但是,事实上没有乙烯醇这样一种单体。alternative tautomeric:互变异构的The appropriate molecular unit exists in the The appropriate molecular unit exists in the alternative alternative tautomerictautomeric form,form,ethanalethanal CH3CHO.To make this polymer,it is CH3CHO.To make this polymer,it is necessary first to prepare necessary first to prepare poly(vinyl ethanoate)poly(vinyl ethanoate)from the from the monomer vinyl ethanoate,and then to monomer vinyl ethanoate,and then to hydrolysehydrolyse the product to the product to yield the polymeric yield the polymeric alcoholalcohol.相应的分子单元以互变异构的形式-乙醛存在。为了制备聚乙烯醇,必需先由乙酸乙烯酯单体制备出聚乙酸乙烯酯,然后对产品进行水解最终制成聚乙烯醇。the degree of polymerization,DP:聚合度P1-3P1-3 The size of a polymer molecule may be defined The size of a polymer molecule may be defined eithereither by by its mass(see Chapter 6)its mass(see Chapter 6)oror by the number of repeat units in the by the number of repeat units in the molecule.This latter indicator of size is called molecule.This latter indicator of size is called the degree of the degree of polymerization,polymerization,DP DP.The.The relative molar massrelative molar mass of the polymer is of the polymer is thus the product of the relative molar mass of the repeat unit and thus the product of the relative molar mass of the repeat unit and the DP.the DP.聚合物分子的尺寸既可以被定义为它的质量也可以被定义为它的分子重复单元的数量。后者被称为聚合度。因此聚合物的相对分子质量是重复单元和聚合度的相对摩尔质量的产物。no clear cut boundary:没有明确的分界线 domain:领域P1-4P1-4 There is There is no clear cut boundaryno clear cut boundary between polymer between polymer chemistry and the rest of chemistry.As a very rough guide,chemistry and the rest of chemistry.As a very rough guide,molecules of relative molar mass of at least 1000 or a DP of at molecules of relative molar mass of at least 1000 or a DP of at least 100 are considered to fall into the domain of polymer least 100 are considered to fall into the domain of polymer chemistry.chemistry.在聚合物化学和其它化学之间不存在严格的界线。作为一个粗陋的指标,分子的相对分子量至少达到1000或聚合度至少100被认为是聚合物化学的范畴。P1-5P1-5 The vast majority of polymers in commercial use are The vast majority of polymers in commercial use are organicorganic in nature,that is they are based on in nature,that is they are based on covalentcovalent compounds compounds of carbon.This is also true of the of carbon.This is also true of the siliconessilicones which,though based which,though based on silicon-oxygen on silicon-oxygen backbonesbackbones,also generally contain significant,also generally contain significant proportions of proportions of hydrocarbonhydrocarbon groups.groups.商业中聚合物的绝大多数分子在性质上是有机分子,也就是说这些聚合物是基于碳原子的共价键化合物。对于硅氧烷聚合物也是如此,尽管它们以硅-氧键为主链,一般也含有大量的烷烃基团。The other elements involved in polymer chemistry most The other elements involved in polymer chemistry most commonly include hydrogen,oxygen,commonly include hydrogen,oxygen,chlorinechlorine,fluorinefluorine,phosphorusphosphorus,and,and sulfursulfur,i.e.those elements which are able to form,i.e.those elements which are able to form covalent bonds,covalent bonds,albeit ofalbeit of some some polaritypolarity,with carbon.,with carbon.albeit of:即使在聚合物化学中其它的元素包括氢、氧、氯、氟、磷和硫,它们中有些是极性元素,但都能与碳形成共价键。perturbations:干扰,扰乱 dipole forces:偶极力,静电力 the electron clouds:电子云P2-1P2-1 As is characteristic of covalent compounds,in addition to As is characteristic of covalent compounds,in addition to primary primary valencevalence forces,polymer molecules are also subject to forces,polymer molecules are also subject to various secondary intermolecular forces.This include various secondary intermolecular forces.This include dipoledipole forcesforces between oppositely charged ends of polar bonds and between oppositely charged ends of polar bonds and dispersion forcesdispersion forces which arise due to which arise due to perturbationsperturbations of of the electron the electron cloudsclouds about individual atoms within the polymer molecule.about individual atoms within the polymer molecule.作为共价键化合物的特性,除了有主价键力之外,聚合物分子也拥有多种第二分子间作用力。这种分子间力包括极性键相反电荷未端的极性力,以及色散力,色散力来源于聚合物分子内单个原子间电子云的扰动。attached to:接近,靠近P2-1P2-1 Hydrogen bondingHydrogen bonding,which arises from the particularly,which arises from the particularly intense dipoles associated with hydrogen atoms intense dipoles associated with hydrogen atoms attached toattached to electronegativeelectronegative elements such as oxygen or nitrogen,is important elements such as oxygen or nitrogen,is important in certain polymers,notably in certain polymers,notably proteinsproteins.Hydrogen bonds have the.Hydrogen bonds have the effect of fixing the molecule in a particular effect of fixing the molecule in a particular orientationorientation.These.These fixed structures are essential for the specific functions that fixed structures are essential for the specific functions that proteins have in the proteins have in the biochemicalbiochemical processes of life.processes of life.氢原子靠近电负性元素如氧或氮,会具有特别强的偶极,由此产生氢键,氢键对有些聚合物比如蛋白质极为重要。氢键具有把分子固定在某个特定取向上的作用。这种固定结构至使蛋白质在生命的生物化学过程中承担起特殊功能是十分必要的。is derived from:衍生于 infer:推断P2-2P2-2 Modern books about polymer chemistry explain that the Modern books about polymer chemistry explain that the word polymer word polymer is derived fromis derived from the Greek words poly meaning the Greek words poly meaning many an meros meaning part.They often then many an meros meaning part.They often then inferinfer that it follows that it follows that this term applies to giant molecules built up of large numbers of that this term applies to giant molecules built up of large numbers of interconnected monomer units.In fact this is misleading since interconnected monomer units.In fact this is misleading since historically the word polymer was coined for other reasons.historically the word polymer was coined for other reasons.THE HISTORY OF THE CONCEPT OF THE MACROMOLECULE关于聚合物化学的现代书藉解释聚合物(polymerpolymer)这个词汇是洐生于希腊单词polypoly,它的意思是很多,单词merosmeros意思是部分。然后这些书推断跟随聚合物这个术语意味着巨大的分子,由大量的相互连接的分子单元构建而成。事实上这是个误解,聚合物这个单词在历史上是为其它原因而构造出来的。identical empirical formulae:相同的经验分子式P2-2 P2-2 The concept of polymerism was originally applied to the The concept of polymerism was originally applied to the situation in which molecules hadsituation in which molecules had identical empirical formulae identical empirical formulae but but very different chemical and physical properties.For example,very different chemical and physical properties.For example,benzenebenzene(C6H6;empirical formula also CH)was considered to be a (C6H6;empirical formula also CH)was considered to be a polymer of polymer of acetyleneacetylene(C2H2;empirical formula also CH).Thus the (C2H2;empirical formula also CH).Thus the word polymer is to be found in textbooks of organic chemistry word polymer is to be found in textbooks of organic chemistry published up to about 1920 but not with its modern meaning.published up to about 1920 but not with its modern meaning.起初聚合的概念被应用于这样的场景,分子具有相同的经验分子式但化学性质和物理性质极其不同。例如,苯(C6H6;(C6H6;经验分经验分子式子式 CH)CH)被认为是乙炔的聚合物被认为是乙炔的聚合物polymerpolymer。(。(C2H2;C2H2;经验经验分子式分子式 CH CH)因此聚合物聚合物polymerpolymer 这个单词在约1920年以前的有机化学教科书中一直都能找到,但却不是现代这个含义。P2-3P2-3 The situation is confused,however,by the case of certain The situation is confused,however,by the case of certain chemicals.chemicals.StyreneStyrene,for example,was known from the mid-,for example,was known from the mid-nineteenth century as a clear organic liquid of characteristic nineteenth century as a clear organic liquid of characteristic pungent odourpungent odour.pungent odour:刺激性气味可这在特定化学里是种被混淆的情形。例如苯乙烯从十九世纪中期就被认定是一种带特殊刺激性气味的纯粹的有机液体。P2-3P2-3 It was also known to convert itself under certain It was also known to convert itself under certain circumstances into a clearcircumstances into a clear resinous resinous solid that was almost solid that was almost odour-odour-freefree,this,this resinresin then being called then being called metastyrenemetastyrene.The formation of.The formation of metastyrenemetastyrene(介苯乙烯)(介苯乙烯)from styrene was described as a from styrene was described as a polymerisationpolymerisation and metastyreneand metastyrene was held to be a polymer of was held to be a polymer of styrene.styrene.resinous:树脂状的 odour-free无气味的也知道苯自身在一定环境下会转化成没有气味的纯粹的树脂状固体。由苯乙烯制得介苯乙烯的形成过程被定义为聚合,且介苯乙烯被称作是苯乙烯的聚合物。akin to:相似had no idea of:无法想象P3-0P3-0 However these terms applied only in the sense that there However these terms applied only in the sense that there was no change in empirical formula despite the very profound was no change in empirical formula despite the very profound alteration in chemical and physical properties.There was no alteration in chemical and physical properties.There was no understanding of the cause of this change and certainly the understanding of the cause of this change and certainly the chemists of the time chemists of the time had no idea ofhad no idea of what had happened to the what had happened to the styrene that was remotely styrene that was remotely akin toakin to the modern view of the modern view of polymerisation.polymerisation.可是这些术语仅仅被用在经验分子式不发生变化的情况下,虽然在化学性质和物理性质上有深刻的改变。改变的原因无从理解,且那个时代的化学家无法想象苯乙烯到底发生了什么变化,这与相似于现代观念中的聚合是如此的遥远。ambiguity:模棱两可 to wait until:一直等到coin:造新词P3-1P3-1 Understanding of the fundamental nature of those materials now Understanding of the fundamental nature of those materials now called polymers had called polymers had to wait untilto wait until the 1920s,when Herman Staudinger the 1920s,when Herman Staudinger coinedcoined the word the word macromoleculemacromolecule and thus clarified thinking.There and thus clarified thinking.There was no was no ambiguityambiguity about this new term it meant large molecule,about this new term it meant large molecule,again from the Greek,and these days is used almost interchangeably again from the Greek,and these days is used almost interchangeably with the word polymer.Strictly speaking,though,the words are not with the word polymer.Strictly speaking,though,the words are not synonymous.synonymous.要理解现在被称为聚合物的这些物质的基本属性还必须等到十九世纪二十年代,在那时StaudingerStaudinger造了个新单词 macromoleculemacromolecule 大分子以正视听。这个新单词的意思是大的分子,这样就不会模棱两可了,macromoleculemacromolecule 也来自于希腊语,并且今天也和polymerpolymer这个单词互换使用。从严格意义上说,这两个单词并不是同义词。There is no reason:没有理由P3-1P3-1 There is no reasonThere is no reason in principle for a macromolecule to be in principle for a macromolecule to be composed of composed of repeating structural unitsrepeating structural units;in practice,however,they;in practice,however,they usually are.Staudingers concept of macromolecules was not at usually are.Staudingers concept of macromolecules was not at all well received at first.His wife once recalled that he had all well received at first.His wife once recalled that he had encountered opposition in all his lectures.encountered opposition in all his lectures.从原理上说没有理由认为大分子一定是重复结构单元组成的,可是,大分子的确常常如此。Staudinger的大分子概念起初并未很好的被人们接受。一次他的妻子回忆过去,说他在所有的讲座中遭到反对。somewhere:某个地方P3-1P3-1 Typical of this opposition was that of one distinguished Typical of this opposition was that of one distinguished organic chemist who declared that it was as if zoologists were organic chemist who declared that it was as if zoologists were told that told that somewheresomewhere in Africa an elephant was found who was in Africa an elephant was found who was 1500 feet long and 300 feet high.1500 feet long and 300 feet high.反对者的一个典型例子是,某位著名有机化学家他声称,大分子好比动物学家们被告知在非洲发现一头大象,它有1500英尺长300英尺高。H.Staudinger的大象bound together:结合在一起ill-defined:欠明了的P3-2P3-2 There were essentially three reasons for this opposition.There were essentially three reasons for this opposition.Firstly,many macromolecular compounds in solution behave as Firstly,many macromolecular compounds in solution behave as colloidscolloids.Hence they were assumed to be identical with the then.Hence they were assumed to be identical with the then known known inorganicinorganic colloids.This in turn implied that they were not colloids.This in turn implied that they were not macromolecular at all,but were actually composed of small macromolecular at all,but were actually composed of small molecules molecules bound togetherbound together by by ill-definedill-defined secondary forces.secondary forces.有三个关键原因致使这些反对态度。首先很多大分子在溶液中的表现很象胶体。因此,他们被认这与已知的无机胶体是相同的东西。反过来这又暗示着他们完全不是大分子,而实际上是由定义不清的第二分子间力结合在一起的小分子组成。pursue:导致-去追寻来 constituent:组成,成分Such thinking led the German chemist C.D.Harries to Such thinking led the German chemist C.D.Harries to pursuepursue the search for the the search for the rubberrubber molecule in the early years of the molecule in the early years of the twentieth century.He used various mild twentieth century.He used various mild degradationsdegradations of natural of natural rubber,which he believed would destroy the colloidal character rubber,which he believed would destroy the colloidal character of the material and yield its of the material and yield its constituentconstituent molecules,which were molecules,which were assumed to be fairly small.He was,of course,unsuccessful.assumed to be fairly small.He was,of course,unsuccessful.这种思潮影响德国化学家HarriesHarries在二十世纪早期去寻找所在二十世纪早期去寻找所谓的谓的 橡胶分子橡胶分子。他使用各种各样天然橡胶的温和的降。他使用各种各样天然橡胶的温和的降解物,在其中他相信破坏了材料的胶体性质并且生成了胶解物,在其中他相信破坏了材料的胶体性质并且生成了胶体的组成分子,此组成分子被认为是非常小的。当然,他体的组成分子,此组成分子被认为是非常小的。当然,他不会成功。不会成功。a single formula for a single compound:单个分子式对单个化合物 means:平均值 discretely:不连续的,离散的,分离的P3-3P3-3 The second reason for opposition to Staudingers hypothesis The second reason for opposition to Staudingers hypothesis was that it meant the loss of the concept of was that it meant the loss of the concept of a single formula for a a single formula for a single compoundsingle compound.Macromolecules had to be written in the form.Macromolecules had to be written in the form(CH2CHX)n,where n was a large number.Moreover,no(CH2CHX)n,where n was a large number.Moreover,no meansmeans were available,or indeed are available,for were available,or indeed are available,for discretelydiscretely separating separating molecules where n=100 from those where n=101.molecules where n=100 from those where n=101.反对StaudingerStaudinger假说的第二个原因是,这意味着失去单个分子式对单个化合物的概念。大分子必须被写成(CH2CHX)n(CH2CHX)n的形式,的形式,这里的这里的n n是个很大的数字。而且,无法得到平均值,或实在为是个很大的数字。而且,无法得到平均值,或实在为了得到平均值,要把了得到平均值,要把n=100n=100的分子与的分子与 n=101 n=101的分子离散的区分的分子离散的区分开来。开来。fractionation:部分,分布 distribution:分布Any such attempted Any such attempted fractionationfractionation always gives a always gives a distributiondistribution of of values of n and,even if the mean value of a fraction is actually values of n and,even if the mean value of a fraction is actually n=100,there are significant numbers of molecules of n=99,n=100,there are significant numbers of molecules of n=99,n=101,and so on.n=101,and so on.任何这种尝试性的分布总是给出n值的分布,即便是某一部分的平均值就是n=100n=100,也仍然有相当一部分分子的n=99,n=101等等。interpretation:解释 throw it out:抛弃at some cost:以某种代价 conspicuously:显著的P4-0P4-0 Now the concept of one compound,one formula,with one Now the concept of one compound,one formula,with one formula being capable of both physical(i.e.spatial)and chemical formula being capable of both physical(i.e.spatial)and chemical interpretationinterpretation,had been developed slowly and,had been developed slowly and at some costat some cost,with,with many long,hard-fought battles.Organic chemists could not many long,hard-fought battles.Organic chemists could not easily easily throw it outthrow it out,particularly in view of the fact that it had been,particularly in view of the fact that it had been so so conspicuouslyconspicuously successful with much of the rest of organic successful with much of the rest of organic chemistry.chemistry.现在一种化合物对应一种分子式、和一种分子式可以是物理(如:空间的)和化学的两种解释的概念,以某种代价伴随着严峻的争论,缓慢的发展起来了。有机化学家不会轻易地抛弃这种观点,部分原因是从实际的观察出发,这种观点在其它有机化学中绝大多数化合物是极其成功的。ill-characterised:难以表征 become used to:习惯于 unpromising:无前途的,没有希望的 dextrous:聪明的,灵巧的 P4-1P4-1 The third reason for opposition lay in the nature of many The third reason for opposition lay in the nature of many of the of the polymeric materialspolymeric materials then known.Not only were they then known.Not only were they apparently apparently ill-characterisedill-characterised,but they were also frequently,but they were also frequently non-non-crystallinecrystalline,existing as,existing as gumsgums and resins.Just the sort of and resins.Just the sort of unpromising media,in fact,from which unpromising media,in fact,from which dextrousdextrous organic organic chemists had chemists had become used tobecome used to extractingextracting(萃取)(萃取)crystallinecrystalline substances of well characterised physical and chemical substances of well characterised physical and chemical properties.properties.反对者的第三个原因在于后来才得知的聚合物材料的许多属性。不仅表现出聚合物难以表征,而且它们也常常不能结晶,以胶状物和树脂状存在。事实上,正是这种没有前途的介质,聪明伶俐的有机化学家们从中习惯于萃取、结晶物质来表征物理和化学性质。inherently:本质上self-esteem:自尊的ToTo accept such resins as accept such resins as inherentlyinherently non-crystallisable and not non-crystallisable and not capable of purification in the traditional sense of the word was capable of purification in the traditional sense of the word was too too much for the much for the self-esteemself-esteem of many professional organic of many professional organic chemists.chemists.对于自以为是的许多资深有机化学家来说,要接受这样一种本质上不可结晶,在传统意义上不能纯化的树脂,是要求太高了。Prevalent:流行的P4-2P4-2 Staudingers original paper opposing the Staudingers original paper opposing the prevalentprevalent colloidal colloidal view of certain organic materials was published in 1920 view of certain organic materials was published in 1920 and contained mainly negative evidence.Firstly,he showed that and contained mainly negative evidence.Firstly,he showed that the organic substances retained their colloidal nature in all the organic substances retained their colloidal nature in all solvents in which they dissolve;by contrast,inorganic colloids solvents in which they dissolve;by contrast,inorganic colloids lose their colloidal character when the solvent is changed.lose their colloidal character when the solvent is changed.StaudingerStaudinger的的原创论文发表于1920年,其中反对了有机材料方面流行的胶体观点并包含了主要的否定性的证据。首先,他展示了有机物质在所有溶解它们的溶剂中会保留胶体的性质;与之相反,无机胶体在溶剂改变的情况下会失去它们的胶体性质。Secondly,contrary to what would have been expected,colloidal Secondly,contrary to what would have been expected,colloidal character was able to survive chemical modification of the character was able to survive chemical
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