In this study, P(St-MAA) seed latex particles were first prepared via soap-free emulsion polymerization of styrene (St) and methacrylic acid (MAA), then the seed particles were allowed to swell with St at room t...In this study, P(St-MAA) seed latex particles were first prepared via soap-free emulsion polymerization of styrene (St) and methacrylic acid (MAA), then the seed particles were allowed to swell with St at room temperature, and the P(St-MAA)/P(St- NaSS) core/shell latex particles were then synthesized via seeded emulsion copolymerization of St and sodium styrene sulphonate (NaSS) using AIBN as initiator in the presence of N,N^-methylenebisacrylamide (BAA, water-soluble crosslinker). Results showed that the polymerization could be carried out smoothly when the ratio of BAA to total monomers was less than 3 mol%, the narrow dispersed P(St-MAA) seed particles with the diameter of 150 nm and the P(St-MAA)/P(St-NaSS) core/shell latexes with the particle size of about 200 nm were synthesized. When the 25/75 mole ratio of NaSS/(St + MAA) and 2 tool% of BAA were used in the seeded emulsion polymerization, the resulted P(St-MAA)/P(St-NaSS) latex product showed a low weight loss after water extraction, and the NaSS unit content in the whole particle and in the shell reached 11.7 mol% and 34.6 mol%, resoectivelv.展开更多
Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed p...Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed particles. The obtained peanut- shaped particles showed a novel internal morphology: PS phase formed one domain which linked to the other domain having PMMA core encased by PS shell.展开更多
Micron-sized nonspherical polymer particles having different morphologies were synthesized by seeded soap-free emulsion polymerization of styrene (St) and ethyleneglycol dimethacrylate (EGDMA, used as a crosslinker...Micron-sized nonspherical polymer particles having different morphologies were synthesized by seeded soap-free emulsion polymerization of styrene (St) and ethyleneglycol dimethacrylate (EGDMA, used as a crosslinker) on spherical, linear polystyrene (PS) seed particles. The morphology of the resulting PS/poly(St-co-EGDMA) particles was dependent on the crosslinker concentration and polymerization temperature.展开更多
Hollow polymer latex particles were prepared by seeded emulsion polymerization. A seed latex consisting of styrene (St), butyl acrylate(BA) copolymer was first prepared, and seeded terpolymerization of St BA MA(methac...Hollow polymer latex particles were prepared by seeded emulsion polymerization. A seed latex consisting of styrene (St), butyl acrylate(BA) copolymer was first prepared, and seeded terpolymerization of St BA MA(methacrylic acid) were then carried out in the absence of surfactant. Final latex was treated by a two step treatment under alkaline and acidic conditions, thus, the particles with hollow structure were obtained. We discussed the effects of pH value, temperature and time in alkali and acid treatment processes on hollow structure within the polymer latex particles and amount of carboxylic group on particle surface. The results show that the hollow polymer latex particles with the largest hollow size can be obtained under a certain condition (pH12.5, 90°C, 3 h in alkali treatment stage and pH2.5, 85°C, 3 h in acid treatment stage).展开更多
A series of poly(2-acetoxyethyl methacrylate)/polystyrene(PAEMA/PS) latex interpenetrating polymer networks(LIPNs) were prepared by seeded soap-free emulsion polymerization of styrene on the crosslinked PAEMA se...A series of poly(2-acetoxyethyl methacrylate)/polystyrene(PAEMA/PS) latex interpenetrating polymer networks(LIPNs) were prepared by seeded soap-free emulsion polymerization of styrene on the crosslinked PAEMA seed particles using an oil-soluble initiator.These PAEMA/PS LIPNs showed a well-defined phase-separated structure with PS phase dispersing in continuous PAEMA phase.The domain size of PS phase was found to depend on the crosslinking degree of PAEMA seed particles and the amount of second-stage styrene monomer.展开更多
Crosslinked x-P(St-MAA) seed latex was first prepared via soap-free emulsion copolymerization of styrene (St) and methyl methacrylic acid (MAA) with divinyl benzene as crosslinker and ammonium persulfate as init...Crosslinked x-P(St-MAA) seed latex was first prepared via soap-free emulsion copolymerization of styrene (St) and methyl methacrylic acid (MAA) with divinyl benzene as crosslinker and ammonium persulfate as initiator, and x-P(St-MAA)/x-P(St-NaSS) core/shell latex particles were then synthesized through a novel seeded emulsion copolymerization of St and sodium styrene sulphonate (NaSS) in the presence of water-soluble crosslinker N,N'-methylene bisacrylamide (BAA) using oil-soluble 2,2-azobis isobutyronitrile as initiator. TEM observation indicated that narrow dispersed core/shell latex particles were obtained, and element analysis showed that NaSS unit content in the whole particle and in the shell reached 22.8 wt% and 51.2 wt%, respectively.展开更多
文摘In this study, P(St-MAA) seed latex particles were first prepared via soap-free emulsion polymerization of styrene (St) and methacrylic acid (MAA), then the seed particles were allowed to swell with St at room temperature, and the P(St-MAA)/P(St- NaSS) core/shell latex particles were then synthesized via seeded emulsion copolymerization of St and sodium styrene sulphonate (NaSS) using AIBN as initiator in the presence of N,N^-methylenebisacrylamide (BAA, water-soluble crosslinker). Results showed that the polymerization could be carried out smoothly when the ratio of BAA to total monomers was less than 3 mol%, the narrow dispersed P(St-MAA) seed particles with the diameter of 150 nm and the P(St-MAA)/P(St-NaSS) core/shell latexes with the particle size of about 200 nm were synthesized. When the 25/75 mole ratio of NaSS/(St + MAA) and 2 tool% of BAA were used in the seeded emulsion polymerization, the resulted P(St-MAA)/P(St-NaSS) latex product showed a low weight loss after water extraction, and the NaSS unit content in the whole particle and in the shell reached 11.7 mol% and 34.6 mol%, resoectivelv.
基金supported by National Natural Science Foundation of China(No.50943028)Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene (PMMA/PS) particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed particles. The obtained peanut- shaped particles showed a novel internal morphology: PS phase formed one domain which linked to the other domain having PMMA core encased by PS shell.
基金partially supported by the National Natural Science Foundation of China(No.50943028)Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Micron-sized nonspherical polymer particles having different morphologies were synthesized by seeded soap-free emulsion polymerization of styrene (St) and ethyleneglycol dimethacrylate (EGDMA, used as a crosslinker) on spherical, linear polystyrene (PS) seed particles. The morphology of the resulting PS/poly(St-co-EGDMA) particles was dependent on the crosslinker concentration and polymerization temperature.
文摘Hollow polymer latex particles were prepared by seeded emulsion polymerization. A seed latex consisting of styrene (St), butyl acrylate(BA) copolymer was first prepared, and seeded terpolymerization of St BA MA(methacrylic acid) were then carried out in the absence of surfactant. Final latex was treated by a two step treatment under alkaline and acidic conditions, thus, the particles with hollow structure were obtained. We discussed the effects of pH value, temperature and time in alkali and acid treatment processes on hollow structure within the polymer latex particles and amount of carboxylic group on particle surface. The results show that the hollow polymer latex particles with the largest hollow size can be obtained under a certain condition (pH12.5, 90°C, 3 h in alkali treatment stage and pH2.5, 85°C, 3 h in acid treatment stage).
基金supported by National Natural Science Foundation of China(No.50943028)Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘A series of poly(2-acetoxyethyl methacrylate)/polystyrene(PAEMA/PS) latex interpenetrating polymer networks(LIPNs) were prepared by seeded soap-free emulsion polymerization of styrene on the crosslinked PAEMA seed particles using an oil-soluble initiator.These PAEMA/PS LIPNs showed a well-defined phase-separated structure with PS phase dispersing in continuous PAEMA phase.The domain size of PS phase was found to depend on the crosslinking degree of PAEMA seed particles and the amount of second-stage styrene monomer.
基金financially supported by the National Basic Research Program of China(No.2014CB932202)
文摘Crosslinked x-P(St-MAA) seed latex was first prepared via soap-free emulsion copolymerization of styrene (St) and methyl methacrylic acid (MAA) with divinyl benzene as crosslinker and ammonium persulfate as initiator, and x-P(St-MAA)/x-P(St-NaSS) core/shell latex particles were then synthesized through a novel seeded emulsion copolymerization of St and sodium styrene sulphonate (NaSS) in the presence of water-soluble crosslinker N,N'-methylene bisacrylamide (BAA) using oil-soluble 2,2-azobis isobutyronitrile as initiator. TEM observation indicated that narrow dispersed core/shell latex particles were obtained, and element analysis showed that NaSS unit content in the whole particle and in the shell reached 22.8 wt% and 51.2 wt%, respectively.