| The recipe of UV-curable adhesive was designed and optimized, the influences to the properties of the gradients was studied in this paper. The evolution of chain transfer constant of the catalyst and the molecular weight and PDI of the polymer during the catalytic chain transfer polymerization of 2-hydroxypropyl methacrylate was also studied.The gradients of the adhesive and the factors influencing the adhesion properties was studied. The results indicated that when the proportion between the oligomer and monomer was 3:1 either in polyurethane-acrylate system or epoxy-acrylate system, the adhesion property of the adhesive was good and the viscosity was well situated. Except for the photo-initiator, the gradients of the adhesive wouldn't absorb the 300~400nm UV-light, the suitable amount of photo-initiator is 2%.The addition of DOP decreased the viscosity of the adhesive due to the plasticizing effect. While it was also found from TEM observation that some of the DOP presented in the adhesive was dispersed well with the form of very small agglomerates in the UV cured film. The tensile strength decreased and on the contrary the tear strength increased with the amount of DOP increased. The most suitable amount of DOP added would be 20phr. With the addition of DOP, the glass transition temperature decreased obviously at first and then ascended slowly, and the change range of Tg didn't exceeded 5℃. After the adhesive was cured for a period in the ambient environment, the strength further increased. Adding epoxy resin to epoxy acrylate adhesive, the strength and viscosity raised at first and then descend, the suitable amount of epoxy resin is 5 phr.The tensile strength and tear strength all increased by adding nano-silica to the recipe of polyurethane-acrylate system, and the viscosity increased simultaneously. It was found from TEM observation that silica was dispersed well in the UV cured film with the form of loose agglomerates, and the size of the agglomerates was 0.1-1 urn. The cure speed of the adhesive became slower because of the absorption of UV-light by nano-silica.The polyurethane-acrylate formed IPN structure with the added HTPB, and the adhesion properties of adhesive enhanced obviously. While with the additional amount of HTBN increasing, the adhesion propertied of adhesive raised at first and then decreased, the most suitable amount of which was 8%. From TEM observation it was found that HTBN dispersed with the form of particle in the cured adhesive. The result of DMA showed that the structure of the adhesive became more regular with the addition of HTBN. The cure speed both decreased with the addition of liquid rubber.Using cobaloxime boron fluoride (COBF) and AIBN as catalyst and initiator respectively, the catalytic chain transfer bulk polymerization of 2-hydroxyporpyl methacrylate (HPMA) was carried out at 60℃ and the low molecular weight polymer with a terminal double bond was prepared. The evolution of the apparent chain transfer constant (Csapp) of COBF during the polymerization was determined by the Mayo equation and the CLD (chain length distribution) equation respectively. At thebeginning of the reaction, the chain transfer constant showed values of up to about 2000, but with the increasing of the monomer conversion, the chain transfer constant decreases and keeps at a value of about 600 for sometime and then decreased again. The most likely cause for the catalyst deactivation is the stable cobalt-carbon bond formed at the first period of the reaction and then reached equilibrium point. When the polymerization proceeds up to middle and high conversion, the chain transfer polymerization is further manipulated by diffusions of polymeric propagating chain and catalyst molecules, and the apparent chain transfer constant fell to value of below 300. It has been found also, that the data determined by the CLD equation are usually lower than that by the Mayo equation, especial at high conversion stage. It is because that both original equations are available for the instantaneous produced polymer or the...
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