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Advanced polymer matrix composites (Advanced Polymeric Composite, APC) with its light weight, high specific strength, high specific modulus, high temperature and strong material - performance design and the rapid development of high-tech materials. The matrix resin is a key factor in determining the composite performance merits. Bismaleimide (BMI) resins both polyimide (PI) of high temperature, resistance to radiation, a variety of excellent characteristics of resistance to moist heat, etc., and there are similar to the epoxy resin (EP) and easy processing properties, in The many ways to meet the requirements of the APC, its foreign demand growth rate of 15% per annum. Unmodified BMI, however, there is a high melting point, poor solubility, high molding temperature brittleness of the cured shortcomings, which hinder the BMI the development and application of key poor toughness, toughening modification of the topics at the forefront of the BMI modified . As a the APC matrix resin must not only have excellent mechanical properties (fracture toughness), heat-resistant, heat-resistant, anti-aging, corrosion-resistant, but also have excellent workability. But the the existing resin main problem is the high temperature performance, heat and humidity resistance, toughness, and processability can not unify. Polysiloxane is an outstanding heat resistance, toughness and dielectric properties of the polymer, is expected to become a thermosetting resin excellent toughener, but the viscosity of the polysiloxane, and BMI poor compatibility, so increasing toughening effect has been difficult to play. The hyperbranched polymer of low stereoregularity is a class structure, mass distribution is wide, the aggregate a large number of compounds of the reactive functional group at the end, having a unique structure and properties, the polymerization conditions are of simple features, has become in recent years the field of polymer material a hot research. Hyperbranched polymers have been used for epoxy toughening modification, but has not yet reported for BMI modified hyperbranched polymers. BMI toughening modified one of the key must take into account the the BMI heat resistance and dielectric properties of hyperbranched polymers can ensure the toughening of BMI based on BMI highlights the heat resistance and excellent dielectric properties The modified is worth exploring scientific issues, and this is precisely the purpose of this research. We select the more common, containing different reactive end groups, with BMI has a different reaction mechanism silicone, respectively, are end groups of the epoxy group, γ-glycidoxypropyl trimethoxy silane (KH560), end groups of the reactive double bonds of γ-methacryloyloxy propyl trimethoxy silane (KH570), as well as the terminal group is amino γ-aminopropyl triethoxysilane (KH550), respectively, by hydrolysis of synthesized three terminal groups for the different reactive groups of the hyperbranched the polysiloxane (HBPSi), in order to not only integrates the hyperbranched polymer, and the characteristics of the polysiloxane, and by a reactive end group to solve the compatibility of the polysiloxane and BMI problems. On this basis, explores the preparation HBPSi modified BMI resin, a comprehensive evaluation of the BMI modified the structure and performance of the system. The experimental data proved, HBPSi adding significantly improve the impact strength, heat resistance, and the system's overall performance greatly improved.
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