In order to enhance the reactivity of the silyl-containing ceramic precursor,a hyperbranched silyl-containing polymer with low viscosity and plenty of terminal vinyl-groups was prepared.A novel AB4 type monomer,bis（N,N-diallylamino）methylsilane,was synthesized first by aminolysis of MeHSiCl2 and then was polymerized via hydrosilylation reaction using H2PtCl6 as the catalyst.The polymerization process was monitored by FT-IR spectroscopy.The polymer product was purified via precipitation using ethyl ether and acetonitrile and was analysed by using（）1H-NMR、（）29Si-NMR and FT-IR spectroscopy.The results indicated that the polymer was hyperbranched polycarbosilazane,and α-hydrosilylation was the main reaction.The degree of branching（DB） of the hyperbranched polymer was 0.56 calculated from the（）29Si-NMR spectrum,and the average molecular weight（Mw）was 13 580 g/mol determined by light scattering method.It was found that there still existed a lot of functional vinyl end groups,which can be used as promising reaction centers for curing or modification of the polycarbosilazane.
A carbosilane dendrimer based macrophotoinitiator（MPI-185） containing benzophenone moiety terminal groups was synthesized by a divergent hydrosilylation/allylation reaction sequence followed by alcoholysis of the silicon chloride end groups.The structure of MPI-185 was characterized by FTIR,（）1H-NMR,（）13C-NMR,and（）29Si-NMR,and its intrinsic viscosity,molecular weight and polydispersity were meassured on by using a GPC complex system.Its reactivity was tested via curing a sensitive epoxy acrylate（EA） resin using FTIR,and the thermal property of films cured was measured by TGA.The results were compared with those of a small molecule photoinitiator（185）.It was found that the curring efficiency of macrophoinitiator（MPI-185） was satisfactory,and the thermal degradation temperature of EA resin cured with MPI-185 was also markedly improved.
Two UV curable hyperbranchend polysiloxanes（Ⅰ and Ⅲ） containing vinyl and allyl end groups and an UV cationic curable hyperbranched polymer Ⅱ-Ep with epoxy end groups,were synthesized via the polyhydrosilylation using AB2 type monomers.All hydrosilylation reactions were catalyzed by（Pt/C） or chloroplatinic acid.Three AB2 type monomers were synthesized via hydrolyzation of functional chlorosilane prepared by using Grignardeagents,and dichlorosilane.The molecular structures of the polymers were characterized by（）1H-,（）29Si-NMR,FTIR and GPC,and the UV-curing behaviors of polymers in different atmospheres and different photoaccelerators were also investigated.
