2024年6月27日发(作者:)

Unit1

essentially the ‘giantness’of the size of the polymer molecule that

makes its behavior different from that of a commonly known chemical compound

such as benzene.

实质上,正是由于聚乙烯的巨大的分子尺寸才使其性能不同于像苯这样的一般化合物

(的性能)。

globules of polyvinyl alcohol firstly absorb water,swell and get distorbed

in shape and after a long time go into solution

.聚乙烯醇颗粒首先吸水溶胀,发生变形,经过很长的时间以后,(聚乙烯醇分子)进

入到溶液中。

r peculiarity is that ,in water,polyvinyl alcohol never retains its original

powdery nature as the excess sodium chloride does in a saturated salt solution.

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。

UNIT2

initiation of the chain reaction can be observed most clearly with radical

or ionic initiators.用自由基型引发剂或离子型引发剂引发连锁反应可以很清楚的进行观

察。

reactions occur through the initial addition of a monomer molecule to

an initiator radical or an initiator ion,by which the active state is transferred from

the added monomer.

这样的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

些活性中心由引发剂转移到被加成的单体上。

UNIT3

1. The net effect of this is that monomer molecules are consumed rapidly

without any large increase in molecular weight.

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。

2. The esterification reaction occurs anywhere in the monomer matrix where

two monomer molecules collide, and once the ester has formed, it, too, can react

further by virtue of its still-reactive hydroxyl or carboxyl groups.

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

有活性的羟基或羧基还可以进一步进行反应。

3. But each polymer molecule that forms still has reactive end groups; hence

the polymerization reaction will continue in a stepwise fashion, with each

esterification of monomers.

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


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