| Polymer material is widely used for damping material because its particular structure which can lose heat easily. Due to their viscoelastic nature, polymers have the ability to absorb the mechanical energy and transform it into heat. Whereas common polymer material's temperature range of high tanδis very close. Moreover, as a useful damping material, it must have a high tanδwith large temperature range. Butyl rubber (isobutylene-isoprene copolymer, IIR) has a high barrier to internal rotation which is consist of a linear C-C main chain with two methyl substituents. During the temper tore region of relaxation transition of a polymer from the glassy state into the highly elastic one, there are not only a a-transition but also a liquid-liquid transition (T11). The tanδpeak of butyl rubber is very broad (covering a temperature range of-60 to 10℃), but above 10℃, the damping function almost lose. Therefore, how to broaden the damping functional region becomes the research direction of high performance butyl rubber. This paper is aimed at preparing broad damping temperature and high tanδmaterials based on IIR.The different curing systems on dynamic mechanical properties of IIR were studied. The results showed that the value of tanδmax of IIR cured with sulfur vulcanization was biggest; the value of tanδmax of IIR cured with sulfide sulfur carrier was smallest, and tanδmoved to low temperature. Wherease the value of tanδmax of IIR cured with 201 resin was middle, tanδmax of IIR moved to high temperature. Therefore, 201 resin can be used as curing system researching IIR with wide temperature range and excellent damping properties.In this paper, different carbon black type and dosage on the dynamic mechanical properties of IIR were studied. The study found, with the carbon black particle size increasing, tanδvalues corresponding to temperature changes little, but the value of tanδmax upward trend was evident, and the glass transition region gradually widened. Therefore, the damping properties of IIR were improved with the carbon black particle size increasing. With the content of N990 carbon black increasing, the glass transition region of cured IIR gradually narrowed, tanδpeak became smaller. When the amount of carbon black N990 was 20 phr, the dynamic mechanical properties of IIR was best.This paper mainly studied the dynamic mechanical properties of butyl rubber hybrided with small organic molecules (201 resin and hindered phenol AO-60). When 201 resin existed in the cross-linking system alone, with the increased use of 201 resin, the tanδpeak of vulcanized rubber shifted to high temperature, and the value of tanδmax decreased. When the hindered phenol AO-60 alone existed in the cross-linking system, AO-60-rich phase was formed in the IIR matrix. Hydrogen bonds which were formed between AO-60 molecules, as well as AO-60 molecules and cross-linking system of the polar groups, leaded to increase cross-linking degree. And molecular chain segments movved difficulty. The resistance was ingcreased, and more energy was consumed. When the two co-exist in the cross-linked system, in addition to 201 resin and AO-60 molecules, the intermolecular cross-linking system having hydrogen bonds, hydrogen bonds also existed between 201 resin molecules and AO-60 molecules. When the hindered phenol was 30 phr and 201 resin was 40 phr, the temperature field is-39℃-96.5℃with tanδvalue higher than 0.3, and the middle tanδpeak value was 0.70. The results showed that the organic hybrid was an effective methord to improve the damping properties of IIR in high-temperature region. |
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