• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.348-354
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• 1998

Cellulose grafted with acrylic acid(AAc) was prepared by radiation grafting technique. The effects of reaction temperature. reaction time, monomer concentration, and the crosslinkers on the AAc grafting reaction on cellulose were examined. The amount of AAc grafted on the cellulose reached maximum at the concentration of 0.75vol% difunctional crosslinker and 1.0vol% trifunctional crosslinker, respectively. In the presence of acid, the amount of AAc grafted on the cellulose was decreased when reaction solution contains difunctional crosslinker, while that was increased when reaction solution contains trifunctional crosslinker. In the grafting reaction of cellulose with AAc and TMETA, mixture containing ferrous sulfate and acid enhanced further AAc grafting yield than mixture containing ferrous sulfate only.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.946-953
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• 1996

The effect of absorbed dose, dose rate, cationic salts and solvent on the grafting yield was evaluated when acrylic acid was grafted onto polypropylene fabric by simultaneous irradiation process. Low dose rate when irradiated with the same absorbed dose led to a high grafting yield. On the other hand, the grafting yield increased with dose rate in case the total irradiation times is equal, and the initial rate of grafting was found to be proportional to be 0.74 power of dose rate. $FeSO_4{\cdot}7H_2O$ was found to be the most effective additive for high grafting yield, while inhibiting homopolymer formation. It was impossible to induce radiation grafting without the addition of the certain amount of salt, but the grafting yield decreased with increasing metallic salt.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.47-50
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• 1985

The physical properties of graft polymerized silk fibre were investigated with various vinyl monomers. 1. The graft polymerization of styrene and methyl methacrylate onto raw silk reduced the tenacity and elongation of raw silk due to fixation of sericin covering silk fibre in, but the styrene grafting was more effective for sericin fixation of raw silk than the methyl methacrylate one. 2. The water absorbability of glycidyl methacrylate grafted silk increased 14.6% greater than that of methyl methacrylate grafted silk at the same degree of grafting polymerization. 3. The degree of grafting polymerization was increased mostly with ethylene glycol methacrylate. The water absorbability of ethylene glycol methacrylate grafted silk was higher than that of glycidyl methacrylate or ethyl acrylate grafted silk. But the grafted silk fabric increased the fabric flexural rigidity which was negatively related with the favorability of fabric hand-touch, as compared with that of nongrafted silk fabric. 4. The evenness of graft polymerization could be improved by agitating the polymerization bath at the fixed interval by reducing the inter size deviation of grafted silk skein and the thickness deviation of grafted silk fabric.

• 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.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.938-945
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• 1996

The present studies are to describe the grafting reaction of styrene in various solvents to polypropylene fabric by the simultaneous method using Co-60. The influence of various factors such as absorbed dose, dose rate, type of solvent, acid and multifunctional monomer were evaluated. At constant absorbed dose, the grafting yield was found to be higher at low dose rate. The initial rate of grafting was found to be proportional to a 0.56 power of dose rate. The inclusion of mineral acid in the grafting solution led to an increase in radiation grafting yield at almost all monomer concentration examined. Multifunctional monomer was also effective to increase grafting yield. The addition of both acid and multifunctional monomer was found to accelerate the grafting yield much more than the separate addition of two additives.

• Applied Chemistry for Engineering
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• v.3 no.3
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• pp.491-498
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• 1992

Graft polymerization of 2-hydroxyethyl methacrylate(HEMA) and styrene, from both their binary and unitary systems, onto polytetrafluoroethylene(PTFE) film was investigated by means of the simultaneous ${\gamma}-ray$ induced method. The effect of various parameters such as monomer concentration, dose rate, absorbed dose, HEMA/styrene feed ratios and the type of diluent on the extent of grafting in unitary and binary systems was studied. It was observed that when unitary HEMA was used for grafting, the grafting extent was very slight, whereas when comonomers were used, a good grafting yield could be obtained. Inclusion of sulfuric acid in the monomer solution resulted in enhanced grafting yields.

• Journal of the Korean Chemical Society
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• v.13 no.4
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• pp.365-371
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• 1969

Ceric salt 를 觸媒로 使用하여 여러 가지 反應條件 下에서 絹布上에 Methancrylamide를 grafting 시키고, Schweitzer 試藥에 依한 溶解性 및 赤外線吸收 스펙트럼을 比較檢討하여 그라프드重合物의 生成을 確認하였다. 그라프트率은 溫度, 反應時間 및 Monomer濃度가 增加함에 따라 增加하였으며 그라프트率은 極大化하는 最適의 pH 値가 있음을 알았다. 그라프트率에 관한 理論式을 誘導하고 그 結果를 檢討하였다.

• Applied Chemistry for Engineering
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• v.10 no.6
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• pp.954-959
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• 1999

Radiation-induced grafting of 2-hydroxyethyl methacrylate(HEMA), acrylic acid(AAc) and methacrylic acid(MAAc) onto polypropylene microfiltration membrane has been studied. The effect of grafting conditions such as solvent composition(MeOH and $H_2O$) and monomer concentration on the grafting yield in investigated. The highest degree of grafting is obtained at a solvent composition of 25% $H_2O$:75% MeOH for HEMA, pure water for AAc and 50% $H_2O$:50% MeOH for MAAc. Modification of the PP membranes with hydrophilic monomers is shown to cause an increase in the water permeation flux of the membranes. It is found that HEMA is the best monomer to increase the water permeation flux and the highest water permeation flux is obtained at 99% degree of grafting. The water permeation flux of AAc-grafted PP membrane and MAAc-grafted PP membrane is very sensitive to environmental pH and $Cu^{2+}$ ion, but the water permeation flux of HEMA-grafted PP membrane scarcely depends on pH and $Cu^{2+}$ ion.

• Elastomers and Composites
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• v.49 no.3
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• pp.181-190
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• 2014

Melt grafting of itaconic acid (IA) onto an ethylene-propylene-diene terpolymer (EPDM) with various organic peroxide initiators was performed. Finding the optimum mixing conditions and concentration of ingredients is critical for effective grafting and optimum properties of grafted materials. This study focused on the effects of mixing conditions (temperature and time), initiator type/concentration and monomer concentration on the grafting degree and efficiency, melt flow index, and gel content of EPDM-g-IA. The initiator, 2,5-dimethyl-2,5-di(tert-butyl peroxy)-hexane (T-101), appeared to meet for the best grafting degree (1.91%). The grafting degree increased markedly by increasing the amounts of monomer IA and initiator T-101. The grafting degree also increased by increasing mixing temperature and time. The optimum monomer and initiator concentrations and reaction temperature and time were found to be about 5wt%/0.05wt% and $160^{\circ}C$/15min, respectively. It was found that the physical properties of EPDM-g-IA were higher than those of the pristine EPDM.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.934-938
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• 1997

Acrylic acid was grafted onto the peroxidized cellulose which was stored at room temperature for 20 days after ${\gamma}$-ray irradiation in air. The effect of acids and metallic salts on the grafting yields was determined. The addition of both the acid and metallic salt was found to accelerate the grafting yield much more than the only metallic salt, and the addition of $FeSO_4{\cdot}7H_2O$ led to much higher grafting yield than that of $CuSO_4{\cdot}5H_2O$. The effect of acid on the grafting yield increased by the order $H_2>SO_4>HCl>HNO_3>CH_3COOH$. With the addition of $H_2SO_4$, the grafting yield rapidly increased up to $7{\times}10^{-2}$M, and then levelled off.