• Elastomers and Composites
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• v.44 no.3
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• pp.308-314
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• 2009

The acrylic rubber was synthesized by emulsion polymerization using n-butyl acrylate, n-butyl methacrylate, acrylonitrile, glycidylmethacrylate, and allyl methacrylate. When the contents of acrylonitrile were increased at fixed amount of crosslinking monomers, the Tg of polymers was increased with the contents of acrylonitrile, Mooney viscosity, hardness, and tensile strength also were increased. But the elongation was decreased due to the reduction of chain flexibility. The addition of the monomer for crosslinking, glycidylmethacrylate whose Tg is $56^{\circ}C$ resulted in the increased Tg of the polymer, and increased Mooney viscosity, hardness, and tensile strength, but the elongation at break was decreased with the glycidylmethacrylate contents. It was shown that this phenominon was attributed to the increment of crosslinking density by glycidylmethacrylate through the measurement of rheometer.

• Journal of the Korean Wood Science and Technology
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• v.25 no.3
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• pp.75-82
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• 1997

To improve the quality of coated paper, the continuous research to the coating components and development of alternative latices is required. Recently, amphoteric latex is getting a great concern due to their changable properties of surface charge through controlling pH and some methods have been tried to prepare amphoteric latices. This study was carried out to synthesize amphoteric latex using seeding polymerization method with low concentration emulsifier. Styrene was used as a main monomer in addition to acrylonitrile for a hydrophilic comonomer. acrylic acid for a anionic comonomer and N,N-dimethylaminoethyl methacrylate for a cationic comonomer. Particle size and viscosity of latex were greatly affected by addition of acrylic acid and ammonium persulfate as an initiator. Negative charge of latex in alkali condition was changed to zero to positive charge in around pH 4.

• Elastomers and Composites
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• v.28 no.3
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• pp.183-190
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• 1993

The radical copolymerization with propagation and depropagation is presented in order to estimate reactivity rate of monomers and $K_{11}$(the equilibrium constant for propagation and depropagation) in the copolymerization of ${\alpha}-methylstyrene-co-methylmethacrylate$ and ${\alpha}-methylstyrene-acrylonitrile$. The value of ${\alpha}-methylstyrene$ and methylmethacrylate and $K_{11}$ are found to be 0.48, 0.47 and 5.0 respectively. The value of ${\alpha}-methylstyrene$ and acrylonitrile and the $K_{11}$ are found to be 0.1251, 0.0577 and 23.8 respectively. The treatment rate constant of ${\alpha}-methylstyrene-co-methylmethacrylate$ and ${\alpha}-methylstyrene-co-acrylonitrile$ in the copolymerization is estimated to be 2.5, 80.72 regardless of monomer feed composition.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.153-154
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• 2006

The development of metal catalysts that can polymerize or copolymerize "polar" $Ch_2=CHX$ monomers by insertion mechanisms would significantly expand the scope of metal-catalyzed polymerization and enable the synthesis of new materials with enhanced properties. We have studied the reactions of single-site olefin polymerization catalysts with vinyl chloride, acrylonitrile, and vinyl ethers, in order to probe monomer coordination trends, insertion rates and regioselectivity, and the structures and reactivity of metal alkyls that contain functional groups on the alpha and beta positions of the alkyl chain. These studies provide insights to the key issues that underlie the "polar monomer" problem. Copolymerization of olefins and selected vinyl ethers has been achieved.

• Journal of the Korean Applied Science and Technology
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• v.19 no.1
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• pp.33-42
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• 2002

Copolymerization of ${\alpha}$-Methylstyrene(AMS) with Acrylonitrile(AN) was carried out with benzoylperoxide(BPO) as an initiator in toluene at $80^{\circ}C$ in a continuous stirred tank reactor. Reaction volume and residence time were 0.6 liters and 3 hours, respectively. The monomer reactivity ratios, $r_{AMS}$ and $r_{AN}$ determined by both the Kele$T{\"{u}}d\"{o}s$ method and the Fineman-Ross method were $r_{AMS}$=0.16(0.14), $r_{AN}$=0.04(0.06). The cross-termination factor ${\Phi}$ of the copolymer over the entire AMS composition ranged from 0.75 to 0.92. The ${\Phi}$ factors of poly(AMS-co-AN) were increased with increasing AMS content. The simulated conversions and copolymerization rates were compared with the experimental results. It was observed that the average time to reach dynamic steady-state was three times the residence time.

• Journal of the Korean Chemical Society
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• v.26 no.3
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• pp.179-187
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• 1982

The copolymerization of N-acryloylpyrrolidone and acrylonitrile was performed in N,N'-dimethylformamide at 50$^{\circ}$C and monomer reactivity ratio was obtained by using IR working curve and Fineman and Ross equation. ($r_1$ = 0.43, $r_2$ = 1.56) It is found that resulting copolymer is good polymeric initiator for anionic graft copolymerization of 2-pyrrolidone. Graft copolymers with polybutylamide (nylon-4) grafts onto poly(NAP-Co-AN) backbone were synthesized and the various effects on the graft copolymerization of 2-pyrrolidone were examined. The rate constants ($K_p$) of graft anionic polymerization at 40 and 50$^{\circ}$C were 2.82${\times}$10 and 2.93${\times}$10(l/mole, min), respectively.

• Applied Chemistry for Engineering
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• v.3 no.1
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• pp.172-178
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• 1992

The graft copolymerization of acrylonitrile(AN) onto chitosan film by using $F^{3+}(FeCl_3{\cdot}6H_2O)$ as a photosensitizer in an aqueous medium was carried out under ultraviolet(UV) irradiation. The grafted copolymer was identified by using IR spectroscopy and scanning electron microscope. The effects of various polymerization parameters involving monomer concentration, photosensitizer concentration, polymerization time and polymerization temperature were investigated. As monomer concentration and photosensitizer concentration were increased, the percent grafting was increased up to limiting value. And also the percent grafting was found to increase by increasing the polymerization time and temperature.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.777-786
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• 1996

Uniform sized-porous poly(acrylonitrile-ethylene glycol dimethacrylate) (PAN) microgels were synthesized by seed polymerization using monodisperse polystyrene seed particles. The effect of weight ratios of monomer/seed (M/S) and diluent/monomer (DIM), concentration of crosslinking agent and the type of diluent was investigated on the formation of PAN microgels. The particle size distribution of PAN microgels was found to be monodisperse in that the weight ratio of M/S is less than 50. More porous microgels were formed and the interstices between small sized interior microspheres present inside of PAN microgels were also smaller with increasing crosslinking agent concentration. Well-developed pore structure was found to be in that weight ratio of D/M is 1 and toluene is used as a diluent.

• Journal of the Korean Chemical Society
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• v.26 no.6
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• pp.421-426
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• 1982

Free radical-initiated copolymerization of diethyl isopropenyl phosphate (DEIPA) with vinyl acetate (VAc) and acrylonitrile (AN) was studied. The monomer reactivity ratios for the monomer pairs, determined at $60^{\cric}C$ using benzoyl peroxide as an initiator, are: ${\gamma}_1$(VAc) = 1.56, ${\gamma}_2$(DEIPA) = 0.44: ${\gamma}_1$(AN) = 15.2, ${\gamma}_2$(DEIPA) = 0.031. The values of the Alfrey-Price constants, Q and e, for DEIPA were calculated to be 0.015 and 0.39, respectively, from the VAc system, and 0.014 and 0.34, respectively, from AN/DEIPA pair. These results indicate that ${\alpha}$-methyl substituent of vinyl phosphate monomer decreases the general reactivity in free radical copolymerization. The intrinsic viscosity and number-average molecular weight of copolymers decreased as their content of DEIPA units increased, indicating a high degree of chain transfer caused by DEIPA, as previously learned in DEVPA system.

• Polymer(Korea)
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• v.38 no.3
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• pp.293-298
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• 2014

We prepared hydrophilic porous supporters for the reinforced composite fuel cell membrane by radiation grafting of acrylonitrile (AN) and hydrophilic sodium allylsulfonate (SAS) into a porous polytetrafluoroethylene (PTFE) supporter. The physicochemical properties of the supporters prepared under various reaction conditions such as molar ratio of SAS/AN, monomer concentration, and irradiation dose were evaluated. FTIR was utilized to confirm the successful introduction of SAS/AN copolymer chains into the porous PTFE. The pores of the porous PTFE film were found to be decreased with an increase in the degree of grafting by using FE-SEM and gurley number. Furthermore, by analyzing the degree of grafting, contact angle, and TBO (toluidine blue O) uptake, the hydrophilicity of the prepared supporters was found to increase with an increase in the degree of grafting.