高分子材料与工程专业英语翻译(3)

高分子专业英语选讲课文翻译资料

separation. Usually it is not simply the reactor outlet stream that is recycled back to the reactor inlet, but it can be. For example in a batch reactor the reacting mixture can be recycled, or pumped around, through a heat exchanger to provide thermal control.

循环反应器出于从一种情况到下一种情况循环变化的目的，在种类上可以是间歇反应器、连续流动搅拌反应器、管式反应器等等。回到较早的观点，在节省粗原料的过程中，许多大规模的商业操作合并了一个或多个循环。这一实践通常导致了杂质的累积，它们依次需要分离。通常不是简单地将反应器的出料返回到入口，当然也可以这样做。例如，在间歇反应器中反应混合物可以回收，或用泵打循环，通过热交换器控制热。

Recycle reactor have also found valuable application in the laboratory and pilot plant because of their special characteristics. At one extreme, in which all of the product is recycled (no net flow), the reactor is the exact equivalent of the well-stirred batch reactor. At the other extreme of no recycle, the reactor is simply the tubular variety. If there is some net flow but the recycle rate is high, the overall reactor performs like a CSTR. Yet the reaction tube itself behaves like differential tubular reactor. This versatility of the recycle reactor can be exploited to great advantage in research and development.

循环反应器由于其特殊的特性在实验室和中试车间也发现了应用价值。一个极端是将所有的产物循环（没有净的流出），此时循环反应器严格等效于全混间歇反应器。另一个极端是没有循环，反应器是简单的管式类。假如有一些净的流出但循环率很高，所有的反应器运行类似于连续流动搅拌反应器。然而反应器本身的 类似于不同的管式反应器。在研究和发展中循环反应器的通用性能够开发出更大的优点（势）。

——Bisio A. , Kabel R L. Scaleup of Chemical Processes. New York: John Wiley & Sons Inc. , 1985. 255~257

T 14 Styrene-Butadiene Copolymer 第十四单元 丁二烯-苯乙烯共聚物

The synthetic rubber industry, based on the free-radical emulsion process, was created almost overnight during World War II. Styrene-butadiene (GR-S) rubber crated at that time gives such good tire treads that natural rubber has never regained this market.

合成橡胶工业，以自由基乳液过程为基础，在第二次世界大战期间几乎很快地形成。那时，丁苯橡胶制造的轮胎性能相当优越，使天然橡胶在市场黯然失色。

The GR-S standard recipe is 丁苯橡胶的标准制法是

组分 丁二烯

重量分数 72

10

组分 过硫酸钾

重量分数 0.3

高分子专业英语选讲课文翻译资料

苯乙烯 十二烷基硫醇

This mixture is heated with stirring and at 50℃ gives conversions of 5%~6% per hour. Polymerization is terminated at 70%~75% conversion by addition of a “short-stop”, such as hydroquinone (approximately 0.1 part), to quench radicals and prevent excessive branching and microgel formation. Unreacted butadiene is removed by flash distillation, and syrene by steam-stripping in a column. After addition of an antioxidant, such as N-phenyl-β-naphthylamine (PBNA) (1.25 parts), the latex is coagulated by the addition of brine, followed by dilute sulfuric acid or aluminum sulfate. The coagulated crumb is washed, dried, and baled for shipment.

混合物在搅拌下50℃加热，每小时转化5%～6%，在转化率达70%～75%时通过加入“终止剂” 聚合反应终止，例如对苯二酚（大约0.1的重量百分含量），抑制自由基并避免过量支化和微凝胶形成。未反应的丁二烯通过闪蒸去除，苯乙烯在萃取塔中通过蒸汽萃取（剥离）。在加入抗氧剂后，例如N-甲基-β-萘胺（1.25的重量百分含量），加入盐水，其次加入稀释的硫酸或硫酸铝后乳液凝胶。凝胶碎片被洗

涤

、

干

燥

并

包

装

装

运

。

25 0.5

肥皂片 水

5.0 180

Fig.14.1 SBR plant flow diagram Courtesy of Hydrocarbon Processing and Petroleum Refiner.

图14.1 丁苯橡胶厂流程图取自烃类加工和石油产品精制

This procedure is still the basis for emulsion polymerization today. An important improvement is continuous processing illustrated in Fig. 14.1; computer modeling has also been described.

今天这种生产过程仍是胶体聚合反应的基础。如图14.1所示一个重要的进步是连续操作；也采用计算机模型描述。

In the continuous process, styrene, butadiene, soap, initiator, and activator (an auxiliary initiating agent) are pumped continuously form storage tanks through a series of agitated reactors at such a rate that the desired degree of conversion is reached at the last reactor. Shortstop is added, the latex warmed with steam, and the unreacted butadiene flashed off. Excess styrene is steam-stripped, and the latex finished as shown in Fig. 14.1.

在连续操作中，苯乙烯、丁二烯、肥皂、引发剂和活化剂（一种助引发剂）用泵从储罐通过一系列

11

高分子专业英语选讲课文翻译资料

的混合反应器，泵送流率根据末釜的转化率控制。加入终止剂，乳液用蒸气加热，未反应的丁二烯被闪蒸。剩余的苯乙烯被蒸气剥离，如图14.1表示乳液完成。

表14.1 冷丁苯胶的典型配方

组分 丁二烯 苯乙烯 特十二烷基硫醇 过氧化二异丙苯 过氧化薄荷烷 硫酸亚铁七水合物

焦磷酸钾 磷酸钠十水合物 乙二胺四乙酸钠 甲醛次硫酸钠

松香酸 水

SBR prepared from the original GR-S recipe is often called hot rubber; cold rubber is made at 5℃ by using a more active initiator system. Typical recipes are given in Table 14.1 At 5℃ ,60% conversion to polymer occurs in 12~15h.

由常规丁苯制法制备的丁苯胶常称作热胶；冷胶通过使用一种更高活性的引发体系在5℃制成。典型的配方在表14.1中给出。5℃、60%转化率、12～15 h聚合物形成。

Cold SBR tire treads are superior to those of hot SBR. Polymers with abnormally high molecular weight (and consequently too tough to process by ordinary factory equipment) can

12

配方1 72 28 0.2 0.08 0.14 0.18 4.0 180

配方2 71 29 0.18 0.08 0.03 0.5 0.035 0.08 4.5 200

高分子专业英语选讲课文翻译资料

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