高分子专业英语选讲课文翻译资料

With BF3 (and isobutylene as the monomer), it was demonstrated that the polymerization is possible only in the presence of traces of traces of water or alcohol. If one eliminates the trace of water, BF3 alone does not give rise to polymerization. Water or alcohols are necessary in order to allow the formation of the BF3-complex and the initiator cation according to the above reactions. However, one should not describe the water or the alcohol as a “cocatalyst”. BF3为引发剂（异丁烯为单体），证明仅在痕量水或乙醇的存在下聚合反应是可以进行的。如果消除痕量的水，单纯的BF3不会引发聚合反应。按照上述反应为了能形成BF3-络合物和引发剂离子水或乙醇是必需的。但是不应将水或乙醇描述成“助催化剂”。

Just as by radical polymerization, one can also prepare copolymers by ionic polymerization, for example, anionic copolymers of styrene and butadiene, or cationic copolymers of isobutylene and styrene, or isobutylene and viny ethers, etc. As has been described in detail with radical polymerization, one can characterize each monomer pair by so-called reactivity ratios r1 and r2. The actual values of these two parameters are, however, different from those used for radical copolymerization.

正与自由基聚合反应一样，通过离子聚合反应也能制备共聚物，例如，苯乙烯-丁二烯阴离子共聚物，或异丁烯-苯乙烯阳离子共聚物，或异丁烯-乙烯基醚共聚物，等等。正如对自由基型聚合已经详细描述过那样，人们可以用所谓的竞聚率r1和r2来表征每单体对。然而，这两个参数的实际意义不同于那些用于自由基共聚合反应的参数。 ---Vollmert B. Polymer Chemistry. Berlin: Sping-Verlag, 1973.163

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高分子专业英语选讲课文翻译资料

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高分子专业英语选讲课文翻译资料

PART B 聚合反应工程 UNIT 11 Reactor types 第十一单元 反应器类型

Reactors may be categorized in a variety of ways, each appropriate to a particular perspective. For example, Henglein (1969) chooses a breakdown based on the source of energy used to initiate the reaction (i.e., thermal, electrochemical, photochemical, nuclear). More common breakdowns are according to the types of vessels and flows that exist.

反应器可以用许多方法分类，各自适用于特定的目的。例如，Henglein（1969）基于用于产生反应的能量来源，即，热量，电化学，光化学，原子核，选择了一种细目分类。更多普通的细目分类是按照所存在的容器和流量的类型。 Batch Reactors 1. 间歇反应器

The batch reactor (BR) is the almost universal choice in the chemist’s laboratory where most chemical processes originate. The reason is the simplicity and versatility of the batch reactor, whether it be a test tube, a three-neck flask, an autoclave, or a cell in a spectroscopic instrument. Regardless of the rate of the reaction, these are clearly low production rate devices. As scale up is desired, the most straightforward approach is to move to a larger batch reactor such as a large vat or tank.

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高分子专业英语选讲课文翻译资料

间歇反应器在化学实验室几乎是一般的选择，大多数的化学过程在那里产生。间歇反应器的原理具简单性和通用性，不管它是一支试管，一个三颈瓶，一个高压釜，还是一个光谱仪器的比色皿。不管反应比例，很清楚这些是低产率设备。当要求放大反应器时，大多直截了当的途径是移至一个较大的间歇反应器如一个较大的大桶或罐。

Commercial batch reactors can be huge, 100 000 gal or more. The cycle time, often a day or more, typically becomes longer as reactor volume increases in order to achieve a substantial production rate with an inherently slow reaction. Fabrication, shipping, or other factors place a limit the size of a batch reactor. For example, transportation capacity can limit the size of a batch reactor for which shop, as opposed to on-site, fabrication of the heat exchange surface is required. This limits the production rates for which batch reactors may be economically utilized. Also, batch reactors must be filled, emptied, and cleaned. For fast reactions these unproductive operations consume far more time than the reaction itself and continuous processes can become more attractive.

商业化的间歇反应器是庞大的，10万加仑或更大。对于慢化学反应，为提高生产率必须增加反应器体积，而这往往导致反应器的循环周期变长，常常以天计算。制造、运输以及其他因素限制了反应器的规模，如热传递能力会限制间歇反应器的尺寸，热交换器必须在制造厂而不是在现场加工。这限制了产率由于这间歇反应器可以被经济地利用。间歇反应器也必须装料、卸料和清洗。为了加快反应这些非生产性的操作消耗了多于反应本身的时间，连续化过程可能更有吸引力。 2. Semibatch Reactors (SBR) 2.半间歇反应器

Some reactions may yield a product in a different phase from the reaction mixture. Examples would be liberation of a gas from a liquid-phase reaction or the formation of a precipitate in a fluid-phase reaction. To drive the reaction to completion, it may be desirable to continuously separate the raw product phase. A semibatch operation may result as well from differing modes of feeding the individual reactants. For reasons we will discuss later, it may be desirable to charge one reactant to the reactor at the outset and bleed a second reactant in continuously over time. Such reactors have both a batch and a flow character and, like batch reactors, are useful for slow reactions and low production rates.

一些反应器可以从反应混合物的不同相态中生产出某种产品。例如液相反应中气体的释放，或流动相反应中沉淀的生成。为了驱使反应完全，希望继续分离粗产物相。个别反应物的不同加入方式也导致半连续操作。原因我们以后讨论，可希望一开始加入一种反应物以后连续加入第二种反应物。这类反应器同时具有一个间歇和一个流动的特征，像间歇反应器，适用于慢反应和低产率。

3. Continuous Stirred Tank Reactors (CSTR) 3. 连续流动搅拌反应器

It is a small step from the batch reactor to the CSTR. The same stirred vessel

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