Amine terminated polyetherimide (AT-PEI) has been synthesized using 2,2'-bis[4-(3,4-dicarboxyphenoxy)-phenyl]propane dianhydride (BPADA) and m-phenylenediamine. Polyetherimide containing pendant carboxy group (CP-PEI) has also been synthesized by the reaction of BPADA, m-phenylenediamine and 3,5-diaminobenzoic acid. The modified PEIs were used as toughening agent for diglycidyl ether of bisphenol-A epoxy resin which was cured with nadic methyl anhydride (NMA). Thermal properties, fracture toughness (KIC) and solvent resistance of toughened epoxy resin were measured. The KIC of epoxy resin containing 20 phr of AT-PEI was 2.88 MPaㆍm0.5 without sacrificing thermal properties. The KIC of epoxy resin which contained 20 phr of CP-PEI was 2.82 MPaㆍm0.5.

사슬 말단에 아민기를 갖는 폴리에테르이미드(AT-PEI)를 2,2'-bis[4-(3,4-dicarboxyphenoxy)-phenyl]propane dianhydride(BPADA)와 m-phenylenediamine의 반응에 의해 합성하였으며, BPADA와 m-phenylenediamine 및 3,5-diaminobenzoic acid의 반응에 의해 pendant 카복시기를 갖는 폴리에테르이미드(CP-PEI)를 합성하였다. 합성된 변성 PEI 들을 bisphenol-A의 diglycidyl ether에 첨가한 후 nadic methyl anhydride(NMA)로 경화시켜 에폭시 수지를 제조하고 열적 특성, 강인성 및 내용매성을 측정하였다. AT-PEI가 20 phr 첨가된 에폭시 수지는 내열의 저하 없이 파괴인성(KIC)가 2.88 MPaㆍm0.5로서 높은 강인성을 보였다. CP-PEI가 20 phr 첨가된 에폭시 수지의 KIC는 2.82 MPaㆍm0.5 이었다.

Keywords: modified polyetherimide; epoxy resin; fracture toughness