• Polymer(Korea)
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• v.24 no.1
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• pp.16-22
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• 2000

Poly(butylene terephthalate- co-oxybenzoate)(PBOT) containing mesogenic oxybenzoate units in the main chain was synthesized through ester exchange reaction by melt mixing of poly(butylene terephthalate)(PBT) and p-acetoxybenzoic acid (ABA). From the kinetics of the copolymerization reaction, the activation energies and the rate constants of homopolymerization and copolymerization, k$_{h}$ and k$_{c}$, could be determined. From the reaction conditions of different compositions, 4/6, 5/5, and 6/4 of PBT/ABA, at 250, 260, and 27$0^{\circ}C$, it was revealed that copolymerization between PBT and ABA proceeds on a pseudo-second order reaction if the ABA content and its conversion are low. In this case, the ratio of rate constants of homopolymerization to copolymerization was in the range from 1.08 to 3.17, indicating that the copolymer with more notable block character was obtained at the higher mole fraction of ABA and at higher temperature.e.e.

• Journal of the Korean Chemical Society
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• v.24 no.1
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• pp.64-72
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• 1980

The synthesis of N-acrylylpyrrolidone has been carried out by the reaction of pyrrolidone and acrylyl chloride. The study on the copolymer of N-acrylylpyrrolidone and styrene is attempted.The copolymerization of N-acrylylpyrrolidone and styrene is carried out in benzene.Monomer reactivity ratio of N-acrylylpyrrolidone and styrene was calculated by Fineman and Ross equation. It is observed that the copolymer of N-acrylylpyrrolidone and styrene has random distributed acyl-lactam function on the vinyl polymer backbone.

• Fashion & Textile Research Journal
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• v.6 no.3
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• pp.384-392
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• 2004

The purpose of this study is in development of effective filter-type polymer adsorbent for removal of pollutants from wastewater by UV irradiation graft polymerization. Photografting of acrylic acid (AA) on polypropylene (PP) nonwoven fabric using benzophenone (BP) as a photosensitizer was investigated. Inhibition of homopolymerization was achieved by adding various concentrations of $FeSO_4{\cdot}7H_2O$, $CuSO_4{\cdot}5H_2O$ and Mohr's salt. As AA concentration was increased, the degree of grafting was increased as to a specific value and then decreased, and the effect of BP concentration showed the same tendency. It was also found that the degree of grafting increased with reaction time and reaction temperature. Addition of the polyfunctional monomers and $H_2SO_4$ to the grafting system accelerated the photografting. The melting temperature, molecular weight and breaking stress and breaking strain were decreased with the increase in the degree of grafting.

• Fashion & Textile Research Journal
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• v.6 no.3
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• pp.377-383
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• 2004

Photografting of styrene (St) on polypropylene (PP) nonwoven fabric using benzoin ethyl ether (BEE) as a photosensitizer was investigated. Inhibition of homopolymerization was achieved by adding various concentrations of $FeSO_4{\cdot}7H_2O$, $CuSO_4{\cdot}5H_2O$ and Mohr's salt. As St concentration was increased, the degree of grafting was increased as to a specific value and then decreased, and the effect of BEE concentration showed the same tendency. It was also found that the degree of grafting increased with reaction time and reaction temperature. Addition of the polyfunctional monomers and $H_2SO_4$ to the grafting system accelerated the photografting. The melting temperature, molecular weight, tensile strength and elongation were decreased with the increase in the degree of grafting.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.127-130
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• 2012

Polymerization of vinyl monomers is promoted by thianthrene cation radical as a part of our research concerning the reactions of various agents with readily isolable, yet highly reactive species and elucidate the biological activity. Thianthrene cation radical initiated the homopolymerization and copolymerization of styrene and ethyl vinyl ether. The polymerization yields decreased as the concentration of phenylacetylene or diphenylethylene increased. Such polymereization by cationic thianthrene radical could provide some clues for the reaction in living animals. Comments on possible polymerization mechanisms were suggested.

• Journal of Integrative Natural Science
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• v.6 no.2
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• pp.71-75
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• 2013

$Bu_3Sn$-endded poly(vinyl)s with biological activity were obtained by the radical polymerization of vinyl monomers using thianthrene cation radical/$^nBu_3H$. Thianthrene cation and stannyl radicals promoted the homopolymerization and copolymerization of styrene and ethyl vinyl ether having number average molecular weights of 2000-3100. Tributyltin hydride functions as a chain transfer agent. Such polymereization by cationic thianthrene and stannyl radicals could provide some clues for the biological reaction in living animals. Plausible polymerization mechanisms were suggested.

• Bulletin of the Korean Chemical Society
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• v.16 no.2
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• pp.138-143
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• 1995

Substituted 3-phenyl-1-silabutanes, 3-chlorophenyl-1-silabutane (1), 3-tolyl-1-silabutane (2), and 3-phenoxyphenyl-1-silabutane (3), were prepared in 68-98% yield by reduction of the corresponding substituted 3-phenyl-1,1-dichloro-1-silabutanes with LiAlH4. The dehydrogenative homopolymerization and copolymerization of the silanes were performed with Cp2MCl2/Red-Al (M=Ti, Hf) catalyst system. The molecular weights of the resulting polymers were in the of range 600 to 1100 (vs polystyrene) with degree of polymerization (DP) of 5 to 8 and polydispersity index (PDI) of 1.6 to 3.8. The monomer silanes underwent the dehydrogenative polymerization with Cp2TiCl2/Red-Al catalyst to produce somewhat higher molecular weight polysilanes compared with Cp2HfCl2/Red-Al catalyst.

• Nuclear Engineering and Technology
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• v.8 no.2
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• pp.89-99
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• 1976

The grafting of acrylic acid in aqueous solution to polyvinyl chloride fibers tab been studied in the presence of ferrous, ferric, and cupric salts, The mutual irradiation technique was adopted using a Co-60 source or a Van do Graaff accelerator. The grafting and homopolymerization were suppressed by the cations. Particularly the grafting was suppressed by the cations in the following order of effectiveness : $Cu^{2+}$>$Fe^{2+}$>$Cu^{3+}$. The rate of grafting (in %/hr) was proportional to the 0.76th power of the dose rate over the range from 8.5f $10^3$ rad/hr to $1.4\times10^5$ rad/dr. The apparent activation energy for the grafting was determined to be 6.1 Kcal/mole between $25^{\circ}$ and $75^{\circ}C$ for the mixture of AA-HaO-$(CH_2Cl)_2$, containing Mohr's salt, $4\times10^{-3}$ mole/l. The increase of the grafting was observed when total dose and dose intensity were raised, or when ethylene dichloride as a swelling agent was saturated in the monomer mixture. The grafted polyvinyl chloride fibers showed considerable improvement in moisture regain, heat shrinkage, and melting properties, but tensile properties were not significantly affected by grafting.

• Carbon letters
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• v.13 no.3
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• pp.133-138
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• 2012

According to kinetic mechanisms, liquid phase polymerization and solid phase polymerization are different in acrylonitrile (AN) polymerization, and so the relationship between the contribution ratio and molecular weight distribution (MWD) was obtained through theoretic analysis. The precipitation homopolymerization of AN was carried out in a mixture solution of dimethyl sulfoxide (DMSO) and water at $50{\sim}65^{\circ}C$ using ${\alpha}$,${\alpha}^{\prime}$-azobisisobutyronitrile as an initiator. The contribution ratio decreased and approached 0; the MWD also decreased and approached 2 with the increase of the $H_2O$/DMSO ratio from 10/90 to 90/10. The experimental data were found to coincide well with the theoretical equation derived from the mechanisms.

• Macromolecular Research
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• v.9 no.3
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• pp.150-156
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• 2001

Polystyrenes(PS) were grafted onto polypropylene(PP) in the PP solution by ultrasonic irradiation-initiated polymerization of styrene. The resulting products consisted of mixtures of homopolymers and PP-PS copolymer because of the homopolymerization of styrene itself and copolymerization with PP. The dependency of the designated polymerization on sonication times was investigated to monitor the evolution lion of the copolymerization. Formation of the PP-PS copolymer was confirmed by FTIR analysis of the reaction products after a proper separation procedure of free PS and PP-PS copolymer. It was found that the tendency for the formation of PP-PS copolymer was closely related with the phase behavior of the PP/styrene mixture which was also influenced by sonication time. In order to verify the effectiveness of the PP-PS copolymer as a compatibilizer for PP/PS blend, melt mixing of PP/PS/PP-PS was performed in a batch mixer. During the mixing, the average torque was higher for the blend containing PP-PS copolymer influencing compatibilization. In accordance with the results from FRIR analysis and torque measurement, the PS domain size remarkably decreased in the PP/PS/PP-PS blend.