Acrylic Polymer Blends And Damping Properties Of The Study

This paper was aimed at preparing broad damping temperature rang, high tanS vibration damping materials. Homopolymer/copolymer blends, LIPN blends and designed Tg copolymer blends were studied separately. Dynamic Mechanical Analysis(DMA) was used to test the damping properties of materials.Various poly(meth)acrylate (PMMA, PEMA, PnBMA, PMA, PEA, PDA) and PS homopolymer or copolymer latexes were prepared via normal emulsion polymerization. These latexes were blent according to the formula, then samples were prepared. The influence of number of ingredients, blends proportion, selection of hard monomer, crosslinking monomer and sample preparing methods to the damping property were investigated. The results show that the blends of PMMA, PEA and PBA with 1:1:1 proportion have the best damping property, whose tan?was above 0.6 over 100℃ range.Half-continuous emulsion polymerization was used to prepare a series latex penetrating polymer network, and the micro-construction of the latex was characterized by transmission electron microscope (TEM). The materials damping properties before and after blending were compared. The influence of bulk sequence, proportion of hard and soft monomer, selection of hard monomer and content of crosslinking agent were studied. In all of the samples, PS/PEA LIPN and LIPN blends of PS/PEA(4:6) + PEMA/PBA(4:6)= 1:1 have the best damping performance, both having a flat damping curve whose temperature range over 110℃ and tan6 is above 0.4.P(MMA-co-BA) and P(St-co-BA) copolymers with designed theoretical Tg were prepared according to FOX formula. But the damping performance of the blends of these copolymers is not very good. The loss areas (LA) of the samples were compared with the theoretical value calculated via group contribution method, and the results were discussed simply.