In the present work the synthesis of phenyl modified polyesters as polyol component for 2-packaged polyurethane coatings were studied. First, the intermediate was obtained by the esterification of trimethylolpropane and benzoic acid. Changing the content of benzoic acid in the intermediate with 5, 10, 15 and 20wt%, 1,4-butanediol, trimethylolpropane, and adipic acid were used for the polycondensation to produce phenyl modified polyesters(BAB -5, -10, -15 and -20). The moles of reactants were determined by maintaining the OH content of 6.5wt% and OH value of 215, which were appropriate for coatings. The polymerization was done at 130∼230℃ for 10∼11 hours and the results were obtained as follows : M_n=860∼1030, M_w=1420∼1860, M_w/M_n=1.65∼1.81, and conversion=85∼90%. It was observed that, in the case of BAB's synthesis, as the content of benzoic acid increases, the average molecular weight and the viscosity of BAB tend to be decreased.

본 연구에서는 2액형 폴리우레탄 도료용의 폴리올쪽 성분으로서 페닐 변성폴리에스테르를 택하여 이를 합성하는 데 중점을 두었다. 즉 트리메틸을 프로판과 벤조산을 에스테르화시켜 중간 생성물을 얻은 후, 중간생성물 속의 벤조산 함량을 5, 10, 15, 20wt%로 변화시키면서 1,4-부탄디올, 트리메틸올프로판 및 아디프산과 축중합하여 페닐 변성폴리에스테르(BAB-5, -10, -l5, -20)를 각각 합성하였다. 동 합성에 있어서 반응물의 몰수는 도료용 물성에 적합한 히드록시 함량 6.5wt%와 히드록시 값 215선을 유지하여 정하였으며, 중합조건은 130∼230℃에서 10∼11시간으로 하여 M_n=860∼1030, M_w=1420∼1860, 다분산도 1.65∼1.81 및 전화율 85∼90%를 각각 얻었다. 또한 BAB류 합성에 있어서 벤조산의 함량이 증가할수록 평균분자량과 내용물의 점도가 점차 저하되는 경향을 나타내었다.

Keywords: 2-packaged; polyurethane coatings; modified polyester