None of the elastomers discussed in the previous section have useful properties until they have been properly formulated. Although some of the science of compounding is understood, much art still remains in preparing technical rubber compositions. In this section, the science and technology of the various ingredients used in rubber are discussed.
Vulcanization and Curing:
An elastomer, as synthesized, is basically a high molecular weight liquid with low elasticity and strength. Although the molecules are entangled, they can readily disentangle upon stressing, leading to viscous flow. Vulcanization or curing is the process in which the chains are chemically linked together to form a network, thereby transforming the material from a viscous liquid to a tough elastic solid. Strength and modulus increase, while set and hysteresis decrease. Various curing systems are used to vulcanize different types of elastomers, but complete coverage is beyond the scope of this chapter. Rather, discussion here is primarily on the curing of general purpose diene elastomers with sulfur, with only brief mention of other cure systems.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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