Ultrasonic Devulcanization of Scrap Tire Rubbers: Science and Engineering

本研究的主要目的是为新型超声波回收轮胎磨砂胶（GRT）技术开发基础知识和设计高容量设备。在早期的研究中发现，通过在特殊装置中施加一定程度的超声振幅，可以打破增强和非增强硫化弹性体中的三维网络，从而在几秒钟量级的短时间内实现脱硫。最理想的结果是，经过超声波处理的GRT变得柔软，从而使橡胶能够单独或与原始橡胶和塑料共混再加工、成型和再硫化。本研究提出了一系列的任务：(1)设计新的GRT连续超声脱硫设备；(2)强超声对模型未填充和炭黑填充的丁二烯、天然、丁二烯和三元乙丙橡胶硫化胶及其组成GRT的混合物的结构和性能的影响；(3)揭示炭黑对各模型橡胶及其混合物超声诱导力学化学反应的影响；(4)研究超声处理对各型号橡胶硫化剂与初炼橡胶共混物再硫化后力学性能的影响；(5)建立最佳工艺条件，获得高力学性能的改性grd基材料；(6)发展橡胶网络降解理论，并开发反应器的计算机模拟，以帮助扩大该过程的规模。

The main objective of this research is to develop basic knowledge and to design the high capacity equipment for the new ultrasonic technology of recycling ground tire rubber (GRT). It has been discovered in the earlier research that through the application of certain levels of ultrasonic amplitudes in special devices, the three-dimensional network in reinforced and non-reinforced vulcanized elastomers can be broken down leading to devulcanization within a short period of time of the order of a few seconds. As the most desirable consequence, ultrasonically treated GRT becomes soft thereby enabling the rubber to be reprocessed, shaped, and revulcanized alone or in blends with virgin rubbers and plastics.The study outlines a series of tasks enabling: (1) the design of new equipment for continuous ultrasonic devulcanization of GRT; (2) the identification of the effect of powerful ultrasound on structure and properties of model unfilled and carbon black filled styrene-butadiene, natural, butadiene, and EPDM rubber vulcanizates and their mixtures which are the constituents of GRT; (3) to reveal the effect of carbon black on the ultrasonically induced mechanochemical reactions in each model rubber and their mixtures; (4) to investigate the effect of ultrasonic treatment of each model rubber vulcanizates on the mechanical properties of their blends with virgin rubber upon revulcanizations; (5) to establish the optimal processing conditions enabling one to obtain the devulcanized GRT-based materials with high mechanical properties; (6) to develop the theory of rubber network degradation and to develop computer simulations of the reactors as an aid to scaling the process.