Synthesis of toluenesulfonate ester derivatives of three dione monoxime and two oxime compounds was attempted as a cationic photoinitiator, however, diacetyl monoxime toluenesulfonate(I) and phenylpropanedione monoxime toluenesulfonate(Ⅱ) could not be synthesized because of their unstability. The order of photodecomposition rate for the synthesized toluenesulfonate derivatives was benzil monoxime toluenesulfonate(Ⅲ) >acetophenone oxime toluenesulfonate(Ⅳ)>benzophenone oxime toluenesulfonate(Ⅴ). This result shows that dione monoxime toluenesulfonate derivatives photodecomposed more efficiently than oxime toluenesulfonate derivatives. The order of photo-crosslinking initial rate of PGMA by these compounds was the same order of their photodecomposition rate but the degree of photo-crossllnking of PGMA increased with increasing concentration of photoinitiator. The results of photo-crosslinking study of PGMA by these compounds revealed that these compounds have typical reaction characteristics of a cationic photoinitiator. A reaction mechanism of photo-crosslinking was proposed on the basis of their pH changes and photoproduct analyses.

양이온 광개시제로서 3종의 dione monoxime과 2종의 oxime 화합물들의 toluenesulfonate ester 유도체들의 합성을 시도한 결과 diacetyl monoxime toluenesulfonate(I)과 phenylpropanedione monoxime toluenesulfonate(Ⅱ)는 생성물이 불안정하여 합성할 수 없었다. 합성된 양이온 광개시제들의 광분해 속도는 benzil monoxime toluenesulfonate(Ⅲ)>acetophenone oxime toluenesulfonate(Ⅳ)>benzophenone oxime toluenesulfonate(Ⅴ)의 순서로서 dione monoxime 유도체가 oxime 유도체보다 광분해효율이 좋았다. 이 화합물들에 의한 PGMA의 초기 광가교반응 속도는 이들의 광분해속도 순서와 일치하였으나 첨가된 개시제의 양이 많으면 많을수록 가교도가 증가하였다. 이 화합물들에 의한 PGMA의 광가교반응은 전형적인 양이온 광개시제의 반응특성을 보였으며 자외선 조사에 따른 pH 변화, 광생성물의 분석결과에 의해 PGMA의 광가교반응 메카니즘을 제안하였다.

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