| In terms of some unique idea, a series of novel damping materials based on polydimethylsiloxane/polyacrylate, with a gradually broadened damping function region, have been successfully prepared by using five technique approaches.One of them, grafting copolymerization of polydimethylsiloxane oligomer with acrylate, was used to make a polyacrylate elastomer with improved compatibility to poly dimethyl siloxane (PDMS). Another method, adopting the different acrylate monomers whose polymers have ladder change Tgs, was employed to produce a polyacrylate elastomer with even damping value in designed temperature range .The next step is to blend and co-vulcanize the resulting elastomers with polydimethySilo-xane or polymethylphenylsiloxane. Consequently, polysiloxare/polyacrylate blending rubbers were manufactured. Finally, through interpenetrating polymer networks, a complex rubber in which the blended rubber servers as the first network and polyacrylate as the second network was derived. In addition, simultaneously interpenetrating polymer networks (SIN) damping materials were originated from polysiloxane oligomer-containing different molar ratio methylphenylsiloxane and different methacrylate.Applying the weight method and FTIR monitor on line, the synthesis reaction procedure of polyacrylate copolymer and SIN was traced. The polymerization mechanism of the functional groups with vulcanizing capability, aid-vulcanization action of BIM as well as the SIN structures were elucidated by 1H NMR and 13C NMR. By using DMA, DSC, AFM, WAXS etc, the maximum damping value, the temperature range of damping functional regions, TA, LA as well as the morphology of the resulting damping materials were characterized. Besides, the paper further touched the research on the relationship of crystallization-melting, transitionrelaxati-on and compatibility with damping properties of polysiloxane/polyacrylate complexdamping materials. The DMA results show that the resulting complex damping materials have no transition peak split, but possess broad and continuous damping functional area. Comparatively, the damping functional area of polyacrylate rubber, about 100?, is the narrowest one in the damping materials, and the blending rubber, about 150?, is wider than that of the polyacrylate rubber, while the sample form IPNs has the widest functional region, its temperature range being 250?. Reasonably, form 1.1 to 0.35,with the broadened functional areas, the maximum damping value shows an opposite change. The SIN has excellent damping properties, and its tan 8 max can reach 1.4- 0.45 in a 80-180? temperature range. The experimental results further demonstrate that the combination of incompatibility polydimethylsiloxane and polyacrylate by co-vulcanization improves the both compatibility and broadens the low temperature and high temperature functional region. While in SIN, to improve microphase structures and damping properties, the design to increase compatibility between two compositions and modulate crosslinking density as well as relative reaction rate of two compositions, is also effective.The research on the effect of liquid-liquid transition of polyacrylate on crystallization-melting of PDMS indicates that above the melting temperature of PDMS, PDMS is reinforced by a special mutual action between p-electron in carbonyl of polyacrylate and 3d orbit in si atom of PDMS, while below the temperature, the PDMS crystal is lessened, which can not completely remove the crystal of PDMS. However, it is the crystallization behavior of PDMS that results in its most segments relaxation being restrained. The phenomenon of PDMS crystallization above -120? disappears when methylphenylsiloxane is introduced to polydimethylsiloxane, where the segments are freed, tan 5 is raised and the Tg even can be broadened to -115 ?.An investigation on the effect of compatibility and forced compatibility discovers something interesting. The transition peak of E" is able to be broadened with the increase compatibility. Simultaneously, the width of tan...
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