• Elastomers and Composites
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• v.8 no.1
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• pp.81-91
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• 1973

• Rubber Technology
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• v.6 no.1
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• pp.10-25
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• 2005

• Polymer Science and Technology
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• v.1 no.4
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• pp.216-226
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• 1990

• Elastomers and Composites
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• v.11 no.1
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• pp.74-83
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• 1976

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.889-894
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• 1999

Preparation of micron size polymer particles which have desired morphology, size, and structure by emulsion polymerization is very difficult due to coagulation of latex particles and formation of second generation particles. But there are attractive merits such as preparation of structural and functional polymer particles in seeded emulsion polymerization. Seeded emulsion polymerization of n-butyl acrylate(BA) was carried out to investigate the effects of stirring rate, reaction temperature, concentration of initiator, emulsifier, and cross-linking agent on the particle size and size distribution. By the combination of suitable reaction conditions, we succeeded in preparing $0.14{\sim}3.67{\mu}m$ diameter of poly(n-butyl acrylate)(PBA) particles using sequential seeded emulsion polymerization.

• Polymer(Korea)
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• v.34 no.1
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• pp.58-62
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• 2010

The acrylic monomers were graft-polymerized to starch as matrix polymer by emulsion polymerization. Viscosity and particle size of the emulsion were increased with starch contents due to interaction with water and particle swelling toward the water phase by hydroxy group of starch. Chemical stability of the emulsion was also increased with enhancement of starch, but water and alkali resistance were reduced with increasing starch contents because of the increasement of hyrophilicity. Opacity of the starch-acrylic emulsion compound containing calcium carbonate was decreased with contents of starch by its intrinsic color. The film of starch-acrylic polymer showed more clear appearance with increasing starch contents owing to enhancement of amorphous state.

• Journal of Adhesion and Interface
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• v.2 no.4
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• pp.10-23
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• 2001

In order to increase the lower values of % grafting and monomer conversion in the emulsion graft polymerization of methylmethacrylate(MMA) onto sodium alginate (SA; a polymer electrolyte) with alginic acid-g-PMMA, the graft polymerization with water soluble (methanol and acetone) and insoluble solvents was carried out using a varity of solvent amounts and agitating rates. And some physical properties of the graft polymer were also investigated. In the polymerizations with water insoluble solvent, there were pronounced improvements in both % grafting and MMA conversion by the promotion of MMA diffusion from the core to the SA adsorpted on the outer layer of particle and that of MMA complex formation with SA. And the effect was larger for the solvents (cyclohexane, decalin) which do not dissolve PMMA. On the other hand, in the polymerization with water soluble solvent, there was an significant increase in MMA conversion and a considerable increase in the % grafting by the destruction of electrical double layer around the SA chains, abstracting the hydrated water in the layer and the effect was more potential in the case of methanol which is a precipitant of PMMA.

• Journal of Adhesion and Interface
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• v.13 no.3
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• pp.101-108
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• 2012

Narrowly dispersed poly(BMA-co-MMA) and PBMA latices (PSD : 1.002~1.008) were synthesized successfully by surfactant-free emulsion polymerization with 2,2' azobis(2-methyl-propionamidine) dihydrochloride (AIBA) and $K_2S_2O_8$ (KPS). The number average particle diameter and the number average molecule weight were found to be 160~494 nm and (1.25~7.55) ${\times}10^4$, respectively. The influences of BMA/MMA ratio, monomer and initiator concentrations, addition of DVB/EGDMA crosslink agent, and polymerization temperature on the polymerization rates and on the particle size and molecular weight were studied. The rate of polymerization increased with increasing MMA concentration in BMA/MMA weight ratio. The particle diameter as well as the polymer molecular weight could be controlled easily by controlling the BMA/MMA weight ratio, monomer concentration, AIBA and KPS concentration, and polymerization temperature.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.886-892
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• 1997

There are many methods to synthesize polystyrene latex. Emulsion polymerization technique is commonly used commercially, but it requires a new technology to replace a traditional polymerization method because of the disadvantage of chemical initiator for environmental pollution. Since free radicals can be produced by ultrasound energy effect, polystyrene latex was synthesized using ultrasound energy instead of chemical initiator. As the ultrasonic irradiation time was increased, average molecular weight was increased and polydispersity was decreased. The degree of polymerization was increased with the concentration of SDS and maximum degree of polymerization was shown at 2wt.% SDS concentration and the reaction temperature of $40^{\circ}C$. During the course of polymerization, molecular weight was repeatedly fluctuated because of occurrence of depolymerization. Narrow molecular weight distribution polystyrene latex having controlled molecular weight was synthesized by controlling ultrasonic irradiation time and the concentration of SDS.

• Proceedings of the Korean Fiber Society Conference
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• 1997.10a
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• pp.102-106
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• 1997