Study On Rubber/Hindered Phenol/Montmorillonite Nanocomposite Damping Materials

As a type of damping material with high efficiency and low cost, polymer/hindered phenoldamping materials has been developed in the past two or three decades. However, dampingmaterials of this type are often of drawbacks of not only narrow high-damping-temperaturerange, but also with poor thermal stability. Furthermore, the added phenol tends to migrate tothe surfaces of the materials due to thermal immiscibility in most cases, which will underminethe damping performances in the long run.The current work proceeds aiming at such drawbacks. Firstly, a type of carboxylatedstyrene butadiene rubber(XSBR) with glass transition temperature(Tg) close to ambienttemperature was chosen as matrix, then proper type of hindered phenol was selected toimprove the damping performance at evaluated temperature. Secondly, different preparingmethods on structure and damping properties was studied. Low temperature dampingperformance was improved by preparing XSBR/epoxidized natural rubber(ENR) blends withdifferent composition and different types of ENR. Thirdly, sodium basedmontmorillonite(MMT) and carbon black(CB) were introduced into the XSBR/ENR/HP1098system to prepare XSBR/ENR/HP1098/MMT/CB nanocomposite damping materials, theeffect of CB and MMT on structure and performance of the material was studied.A kind of hindered phenol which has never been reported using in damping materialspreparation was chosen to prepare XSBR/HP1098damping materials. Compared withconventional HP1010, the XSBR/HP1098increased the high-damping-temperaturerange from15.1~74.1°C to17.2~87.8°C, tand-T curve integration area increased from39.5to52.4,indicating superior damping performance. Comparing direct blending, melt blending and latexblending methods in preparing XSBR/HP1098/MMT nanocomposite damping material, meltblending and latex blending methods was found to be favourable to prepare samples withMMT galleries forming intercalated and/or exfoliated structure, and later prepared the samplewith highest damping performances; melt method was unparallel in preparing samples withbetter extraction resistance. MMT and HP1098mutually promote dispersing in the matrix,and the introduction of MMT improved the retention rate to7.73wt.%to3.64wt.%.The study on ENR/hindered phenol damping material indicated that ENR50showed bettermiscibility with HP1098. The high-damping-temperature range increased from9.6~55.0°Cfor XSBR to-24.5~52.6°C for XSBR/ENR50when the weight ratio of two components was6:4. The incorporation of60phr of HP1098in the XSBR/ENR50system decreased the widthof high-damping-temperature range from76.6°C to65.1°C while increasing the tand-T integration area from48.5to69.5, indicating distinct improvement in damping performance.Latex method was utilized to disperse6phr of MMT and60phr of HP1098into XSBRmatrix to prepare XSBR/ENR50/HP1098/MMT damping material, and MMT was dispersedin nanoscale; and the onset decomposition temperature elevated by24.2°C spontaneously. Theintroduction of N220dramatically increased the mechanical properties and the retention rateto52.55wt.%from7.42wt.%, meanwhile the onset decomposition temperature was increasedby29.0°C, and XSBR/ENR50/HP1098/MMT/CB nanocomposite damping material withexceptional comprehensive performance was prepared.