In this paper electron beam-curable prepolymers were prepared by the addition reaction of p-t-butylphenol formaldehyde resin with glycidyl methacrylate, and electron beam curing was studied for the prepolymers and their mixtures of several kind of vinyl monomers. When the reaction was carried out in the presence of triethylbenzyl ammonium chloride catalyst without solvent, the rate of the addition reaction obeyed first-order kinetics. Electron beam-curing was carried out at a dose rate of 3 Mrad/sec. It was found that the prepolymer could be cured at a dose of 2 Mrad and when the mixtures of prepolymers containg 30% monomer, the rate of gel formation increased in the order 2-ethyl hexyl methacrylate < styrene < butyl acrylate < ethyl acrylate. In the curing of the mixtures of prepolymer with polyethylene glycol dimethacrylates, maximum gel formation was observed at 10% monomer content at a dose 1 Mrad. However, maximum gel formation was observed at higher monomer content as the total dose increased. In this case the rate of gel formation increased with the increase in the degree of polymerization of the polyethylene oxide fraction of the polyethyleneglycol dimethacrylate.

본연구에서는 p-t-부틸페놀-포름알데히드수지에 메타크릴산 글리시딜을 부가시켜 전자선 경화성 prepolymer를 합성하여 전자선 조사를 하였으며 또 이 prepolymer에 여러가지의 비닐화합물들을 첨가한 혼합물을 전자선 조사하여 경화시켰다. 부가에 의한 prepolymer의 합성반응은 염화 벤질 트리에틸 암모늄을 촉매로 하고 용매없이 진행시켰을때 1차반응에 해당하였다. 이 prepolymer를 선량율 3Mrad/sec에서 전자조사시킬 때 조사선량 2Mrad에서 경화가 가능하였다. Prepolymer에 몇가지의 비닐화합물 30%를 첨가한 혼합물들을 전자선조사한 결과, 겔화속도는 메타크릴산 2-에틸헥실<스티렌<아크릴산부틸<아크릴산에틸의 순으로 증가하였다. Polyethyleneglycol dimethacrylate를 prepolymer에 혼합하여 전자선경화시킬 경우, 1Mrad의 조사선량에서는 dimethacrylate 함량이 10%일 때 최고의 겔 분율을 나타내나 선량이 증가할수록 고농도 범위에서 나타났다. 중합도가 다른 dimethacrylate의 prepolymer와의 혼합물을 전자선 조사한 결과 중합도가 증가하면 겔화속도도 증가하였다.

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