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In this study, ammonolyzed poly(styrene-alt-maleic anhydride) terminated with dithioester group can be self-assembled into an amphiphilic macro-reversible addition-fragmentation chain transfer (RAFT) agent, and RAFT group will be located in the interface of oil and water. RAFT polymerization of styrene (S) and butadiene (B) will be confined in the interface. The main work is to study the effect of degree of aminolysis, reaction temperature, and ratio of S/B on the polymerization kinetics and living characters. The experimental results revealed that aminolysis of dithioester group would lead to retardation and loss of living characters under higher degree of aminolysis. Interfacially confined RAFT miniemulsion polymerizations were of relatively good controlled/living characters under lower degree of aminolysis before gelation. Increase of reaction temperature and ratio of S/B will accelerate the formation of gelation. Finally, styrene/butadiene copolymer nanoparticles with uniform particle size were formed, and because of microphase segregation ''core-shell'' morphology with polybutadiene core and polystyrene shell was seen obviously.

a-Butyl-x-N,N-dihydroxyethylaminopropylpolydimethylsiloxane, a monotelechelic polydimethylsiloxane with a diol-end group, which is used to prepare polyurethane-polysiloxane graft polymer, was successfully synthesized. The preparation included five steps, which are hydroxyl protection, alkylation, anionic ring-opening polymerization, hydrosilylation, and deprotection. The products were characterized by FTIR, GC, LC-MS, 1 H NMR, and elemental analysis. The results showed that each step was successfully carried out and the targeted products were synthesized in all cases.

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In this study, a,x-bis(3-(1-methoxy-2-hydroxypropoxy)propyl)polydimethylsiloxane and a-N,N-dihydroxyethylaminopropyl-x-butylpolydimethylsiloxane were used to prepare block and graft waterborne polyureathanepolysiloxane copolymer dispersions. a,x-bis(3-(1methoxy-2-hydroxypropoxy)propyl)polydimethylsiloxane was synthesized by hydrosilylation, methoxylation and equilibrium reactions; a-N,N-dihydroxyethylaminopropylx-butylpolydimethylsiloxane was synthesized via hydroxyl protection, alkylation, anionic ring-opening polymerization, hydrosilylation, and deprotection. Block and graft waterborne polyurethane-polysiloxane copolymer dispersions were prepared by the reaction of poly-(propylene glycol) (PPG), toluene diisocyanate (TDI), 2,2dimethylol propionic acid (DMPA), 1,4-butanediol (BDO), a,x-bis(3-(1-methoxy-2-hydroxypropoxy)propyl)polydimethylsiloxane, and a-N,N-dihydroxy-ethylaminopropyl-xbutylpolydimethylsiloxane. The water absorption of block and graft waterborne polyurethane-polysiloxane copolymer films decreased from 163.9 to 40.2% and 17.3%, respectively, when percent of polysiloxane (w=w) increased from 0 to 5%, and the tensile strength of the block waterborne polyurethane-polysiloxane copolymer films decreased while the tensile strength of graft waterborne polyurethane-polysiloxane copolymer films increased with increase of percent of polysiloxane. For graft waterborne polyurethane-polysiloxane films, the tensile strength would decrease when percent of polysiloxane was more than 3%. POLYM. ENG. SCI., 54:805-811, 2014.