Phenolic vulcanization of butadiene nitrile rubber. 1. Investigation of mechanism of vulcanization by infrared spectroscopy

Vulcanization and the Properties of Rubber

Rubber is composed of long stringlike polymer molecules, which are pinned together at random points by crosslinks. As the density of crosslinks is increased, the molecules get localized and the system undergoes a phase transition from a liquid to an amorphous solid state. The elastic properties of the resulting solid are very different from those of metals, and are primarily due to changes in t...

Theory & Practice Of Vulcanization

investigation of effective parameters on the rigidity of light composite diaphragms (psscb) by fem

در این رساله با معرفی سقف های psscb متشکل از ترکیب ورق های فولادی ذوزنقه ای و تخته های سیمانی الیافی به عنوان سقف های پیش ساخته (سازگار با سیستم سازه ای قاب های فولادی سبک) به بررسی پارامترهای موثر بر صلبیت سقف، پرداخته می شود. در تحقیق حاضر ابتدا به مدل سازی دو نمونه سقف آزمایش شده، به روش اجزاء محدود با استفاده از نرم افزار تحلیلی abaqus ver 6.10 پرداخته شده است. نمونه های ساخته شده تحت اعما...

From Vulcanization to Isotropic and Nematic Rubber Elasticity

– A Landau theory is constructed for the vulcanization transition in cross-linked polymer systems with spontaneous nematic ordering. The neo-classical theory of the elasticity of nematic elastomers is derived via the minimization of this Landau free energy; this neoclassical theory contains the classical theory of rubber elasticity as its isotropic limit. Our work not only reveals the statistic...

Characterization of free volume during vulcanization of styrene butadiene rubber by means of positron annihilation lifetime spectroscopy and dynamic mechanical test.

An experimental investigation was performed to study the effect on the free volume of the advance of the cross-linking reaction in a copolymer of styrene butadiene rubber by sulfur vulcanization. The dynamic modulus and loss tangent were evaluated over samples cured for different times at 433 K by dynamic mechanical tests over a range of frequencies between 5 and 80 Hz at temperatures between 2...