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具有从中等到较低结晶度的聚合物常常适用于缨状微束理论作为两相体系来处理，这些体系是由微晶包埋在非结晶的无定形聚合物中而构成的。

The fringed-micelle and folded-chain theories of polymer crystallinity are often considered to be mutually exclusive but they need not be so considered.

经常认为聚合物结晶的缨状胶束和折叠链理论是相互排斥的，其实不是这样的。 It is usually practical to adopt a working model of polymer crystallinity which employs the features of both concepts.

实际工作中常采用聚合物结晶性的工作模型，这个模型兼有两者的特征。

The folded chain theory is especially well suited for highly crystalline polymers where one can consider them to be one phase crystalline systems with defects. 折叠链理论特别适用于高结晶聚合物，高结晶聚合物被认为是具有缺陷的单相结晶体系。

Polymers with medium to low crystallinity can often be advantageously treated by the fringed micellel concept as two phase systems composed of crystallites imbedded in uncrystallized，amorphous polymer.

具有从中等到较低结晶度的聚合物常常适用于缨状微束理论作为两相体系来处理，这些体系是由微晶包埋在非结晶的无定形聚合物中而构成的。

UNIT 9 Structure and Properties of Polymers

Most conveniently, polymers are generally subdivided in three categories, [namely]viz., plastics, rubbers and fibers.

聚合物一般细分为三种类型，就是塑料，橡胶和纤维。

In terms of initial elastic modules, rubbers ranging generally between 106 to 107dynes/cm2, represent the lower end of the scale, while fibers with high initial moduli [modjulai, modulus的复数] of 1010 to 1011dynes/cm2 are situated on the upper end of the scale; plastics, having generally an initial elastic modulus of 108 to 109dynes/cm2, lie in-between.

就初始弹性模量而言，橡胶一般在106到107达因/平方厘米，在尺度的低端，而纤维具有高的初始模量，达到1010到1011达因/平方厘米，在尺度的高端，塑料的弹性模量一般在108到109达因/平方厘米，在尺度的中间。

As is found in all phases of polymer chemistry, there are many exceptions to this categorization

在高分子化学的各个方面，我们发现这种分类方法有许多例外的情况。

An elastomer (or rubber) results from a polymer having relatively weak interchain forces and high molecular weights.

弹性体是具有相对弱的链之间作用力和高分子量的聚合物。

When the molecular chains are ‘straightened out’ or stretched by a process of extension, they do not have sufficient attraction for each other to maintain the oriented state and will retract once the force is released. 当通过一个拉伸过程将分子链拉直的时候，分子链彼此之间没有足够的相互吸引力来保持其定向状态，作用力一旦解除，将发生收缩。

However, if the interchain forces are very great, a polymer will make a good fiber.

然而，如果分子链之间的力非常大，聚合物可以用做纤维。

Therefore, when the polymer is highly stretched, the oriented chain will come under the influence of the powerful attractive forces and will “crystallize” permanently in a more or less oriented matrix.

因此，当聚合物被高度拉伸的时候，取向分子链将受强引力的影响在有取向的基体中“永久地结晶”。

These crystallization forces will then act virtually as crosslinks, resulting in a material of high tensile strength and high initial modulus, i.e., a fiber. 这些结晶力实际上以交联方式作用，产生高拉伸强度和高初始模量的材料，即纤维。 Therefore, a potential fiber polymer will not become a fiber unless subjected to a 'drawing' process, i.e., a process resulting in a high degree of intermolecular orientation. 因此，可以制成纤维的聚合物将不成其为纤维，除非经受一个抽丝拉伸过程，即一个可以形成分子间高度取向的过程。

Crosslinked species are found in all three categories and the process of crosslinking may change the cited characteristics of the categories.

交联的种类在所有三种类型（塑料，橡胶，纤维）中找到，而交联过程可以改变各类的典型特征。

Thus, plastics are known to possess[p?zes] a marked range of deformability in the order of 100 to 200%; they do not exhibit this property when crosslinked, however.

因此，我们熟知塑料具有的形变能力大约在100-200%范围内，然而当交联发生时塑料不能展示这个性能。

Rubber, on vulcanization, changes its properties from low modulus, low tensile strength, low hardness, and high elongation to high modulus, high tensile strength, high hardness, and low elongation.

对橡胶而言，硫化可以改变其性质，从低模量，低拉伸强度，低硬度及高拉伸率到高模量，高拉伸强度，高硬度及低拉伸率。

Thus, polymers may be classified as noncrosslinked and crosslinked, and this definition agrees generally with the subclassification in thermoplastic and thermoset polymers. 这样，聚合物可以分为非交联和交联的，这个定义与把聚合物细分为热塑性和热固性聚合物相一致。

From the mechanistic point of view, however, polymers are properly divided into addition polymers and condensation polymers. Both of these species are found in rubbers, plastics, and fibers.

然而，从反应机理的观点看，聚合物可以分成加聚物和缩聚物。这些种类聚合物在塑料，橡胶和纤维中都可以找得到。

In many cases polymers are considered from the mechanistic point of view. Also, the polymer will be named according to its source whenever it is derived from a specific hypothetical monomer, or when it is derived from two or more components which are built randomly into the polymer.

在许多情况下，聚合物可以从反应机理的角度考虑分类。也可以根据聚合物的的来源来命名,无论来源是一个假想单体，或来自于两个或两个以上无规构建聚合物的组分。

This classification agrees well with the presently used general practice.

这种分类方法与目前实际情况相符合。

When the repeating unit is composed of several monomeric components following each other in a regular fashion, the polymer is commonly named according to its structure.

当重复单元由几个单体组分规则排布时，聚合物通常根据它的结构来命名。

It must be borne in mind that, with the advent of Ziegler-Natta mechanisms and new techniques to improve extend crystallinity, and the cIoseness of packing of chains, many older data given should be critically considered in relation to the stereoregular and crystalline structure.

“必须记住，随着Ziegler-Natta机理的，以及提高结晶度和链堆砌紧密度新技术的出现， 许多与立构规整和晶体结构相关的旧数据应当批判地接受。

The properties of polymers are largely dependent on the type and extent of both stereoregularity and crystallinity. As an example, the densities and melting points of atactic and isotactic species are presented in Table 9.1.

聚合物的性质主要依靠立体规整性和结晶度的类型和程度。表9.1列出无规立构和全同立构物质的密度和熔点。

UNIT 10 Glass transition temperature

An ordinary rubber ball if cooled below -70°C becomes so hard and brittle that it will break into pieces like a glass ball falling on a hard surface! Why does a rubber ball become like glass bellow -70°C?

一个普通的橡胶球被冷却到零下70度以下，就会变得又硬又脆，掉在硬表面上就会像玻璃球一样破碎成碎片。为什么橡胶球在零下70度以下就变得像玻璃一样了？ This is because there is a “temperature boundary” for almost all amorphous polymers (and many crystalline polymers) only above which the substance remains soft, flexible and rubbery and below which it becomes hard, brittle and glassy.

这是因为几乎所有无定型聚合物(及许多结晶聚合物)都有一个“温度边界”，温度高于这个边界，材料保持软的柔韧的及橡胶状的，而高于这个边界，材料则变成硬的，脆的，玻璃状的。

This temperature, below which a polymer is hard and above which it is soft, is called the “glass transition temperature” Tg.

这个温度，低于这个温度聚合物是硬的，高于这个温度聚合物就是软的，这个温度就叫玻璃化温度，Tg.

The hard, brittle state is known as the glassy state and the soft, flexible state as the rubbery or viscoelastic state. Be known as： 叫做 硬的，脆的状态叫做玻璃态，软的，柔韧的状态叫做橡胶态或粘弹态。

On further heating, the polymer (if it is uncross-linked) becomes a highly viscous liquid and starts flowing: this state is termed viscofluid state, and the another transition takes place at its flow temperature Tf. 进一步加热，聚合物（如果它是非交联的）就变成高粘性液体而开始流动，这个状态叫做粘流态，另一个转变发生在聚合物流动温度上。

Now, let us consider a polymer, say, polyethylene. At room temperature, polyethylene is solid, exhibiting all characteristics of a low molecular weight substance.

现在让我们考虑一下一个聚合物，叫聚乙烯。在室温下，聚乙烯是固体的，展现低分子量化合物的所有特征。

At high temperatures, however, the characteristic difference between high and low molecular weight substances can be seen.

然而，在高温下高分子量和低分子量物质之间的区别是显而易见的。

Depending on the temperature, the molecules of a low molecular weight substance either move apart as a whole or do not move at all. i. e., there is a definite temperature(melting point Tm) below which the molecules do not move and above which they do move.

根据温度, 低分子量的物质要么整个分子移开，要么根本不运 动。有一个特定的温度(熔点Tm)在低于这一温度时分子不运动，而在高于这一温度时分子则在运动。 On the other hand, with polymers, if the temperature increases above Tg, localized units (chain segments) within the long chain molecule are first mobilized before the whole molecule starts moving.

对聚合物而言，另一方面，如果温度增加超过玻璃化温度，在整个长分子链内的局部单元（链段）在整个分子运动之前首先动起来。

In some parts within the molecule, there is a considerable localized motion, but not in other parts of the same molecule.

在这个分子的一部分有比较大的局部运动，而相同分子的另一部分则没有运动。 Thus, within the long chain of the polymer molecules, some segments have a certain freedom of movement, whereas others do not.

因此，在聚合物分子的长链内，一些链段有一定的运动自由度，而其它的链段则没有。

The molecule as a whole does not move although some of its segments do. In the case of polymers, there is indeed an intermediate state.

尽管分子的一些链段在动，分子整体是不动的。聚合物有一个中间状态。

If the temperature ranges between Tg and Tf, the localized mobility is activated, but the overall mobility is not.

如果温度在Tg 和Tf之间，局部的运动被激活，而整体的运动则没有。

The local segments, where mobility is already activated, correspond to the liquid state, while the molecule as a whole, where mobility is forbidden, is in the solid state. This state, which is really a combination of liquid and solid, is called the rubbery state.

局部链段的运动被激活，对应着液态，而整个分子的运动性受到限制，则仍处于固态。这个状态，实际上是液态和固态的结合，叫做橡胶态。

Under the influence of an applied stress, it exhibits properties of a viscous fluid as well as an elastic solid and undergoes what is called viscoelastic deformation.

在外加应力的作用下，聚合材料既显示出粘性液体的性质，也显示出弹性固体的性质，而经历的过程叫做粘弹形变。

The glass transition temperature Tg is an important parameter of a polymeric material. The Tg value of a polymer decides whether a polymer at the “use temperature” will behave like rubber or plastics.

玻璃化转变温度Tg是聚合物材料的重要参数。聚合物的Tg决定聚合物在使用温度下究竟是体现橡胶的还是塑料的行为。

The Tg value along with the Tm value gives an indication of the temperature region at which a polymeric material transforms from a rigid solid to a soft viscous state。

Tg值和Tm值表明了一个温度范围，在这个范围内聚合材料由刚性固体转化为柔软的粘流态。

This helps in choosing the right processing temperature, i.e., the temperature region in which the material can be converted into finished products though different processing

techniques such as moulding, calendering, extrusion, etc. 这可以帮助我们选择正确的加工温度，即通过不同的加工技术，如模塑，压延，挤出等，材料可以转变成最终产品的温度范围。

UNIT 11 Functional Polymers

Functional polymers are macromolecules to which chemically functional groups are attached; they have the potential advantages of small molecules with the same functional groups.

功能聚合物是具有化学功能基团的大分子，这些聚合物与具有相同功能基团的小分子一样具有潜在的优点。

Their usefulness is related both to the functional groups and to the nature of the polymers whose characteristic properties depend mainly on the extraordinarily large size of the molecules.

它们(功能聚合物)之所以具有使用价值不仅与所带的官能团有关，而且与由巨大的分子尺寸所决定的聚合物的特性有关。

The attachment of functional groups to a polymer is frequently the first step towards the preparation of a functional polymer for a specific use.

把功能基团连接到聚合物上常常是制备特殊用途功能高分子的第一步。

However, the proper choice of the polymer is an important factor for successful application.

然而，对成功应用而言，选择适当的聚合物是一个重要因素。

In addition to the synthetic aliphatic and aromatic polymers, a wide range of natural polymers have also been functionalized and used as reactive materials.

除了合成的脂肪族和芳香族聚合物之外，许多天然高分子也被功能化，被用做反应性材料。

Inorganic polymers have also been modified with reactive functional groups and used in processes requiring severe*si’vi?] service conditions.

无机聚合物也已经用反应功能基团改性，被用于要求耐用条件的场合。

In principle, the active groups may be part of the polymer backbone or linked to a side chain as a pendant group either directly or via[vai?+ a spacer*s’peis?] group.

理论上讲，活基团可以是聚合物主链上的一部分，直接作为侧基或者通过隔离基团连接到侧链。

A required active functional group can be introduced onto a polymeric support chain (1) by incorporation during the synthesis of the support itself through polymerization or copolymerization monomers containing the desired functional groups, (2) by chemical modification of a non-functionalized performed support matrix and (3) by a