ABA type block copolymers composed of nylon 6 (A) and poly (tetramethylene oxide) (PTMO)(B) were synthesized by anionic polymerization of ε-caprolactam (CL) using prepolymer (α, ω-diisocyanated PTMO) as chain initiator. The mechanical properties and morphologies of nylon 6/PTMO block copolymer and nylon 6/plasticizer system were investigated. Maximum stress and modulus of elasticity decreased linerly with increasing PTO and plasticizer content. Strain at break showed little change up to 6 wt% of PTMO and plasticizer, and increased dramatically when the PTMO content is more than 6 wt%. Low temperature (-30 ℃)impact test results showed little change, however, room temperature test showed an increase in notched Izod impact strength with increasing PTMO and plasticizer content. SEM observation of the room temperature impact fractured surface showed an increased fibrillar structure with increasing PTMO content.

Poly(tetramethylene oxide)(PTMO)의 양말단을 이소시아네이트로 치환한 프리폴리머를 사슬개시제로 사용하여 캐스팅 기법에 의하여 ε-caprolactam (치)을 음이온 중합시키므로써, 나일론 6-PTMO-나일론 6 형태의 블록 공중합체를 합성하였다. PTMO와 가소제의 함량 변화에 따른 공중합체의 기계적 물성과 모폴로지의 변화를 관찰한 결과, 최대 응력과 탄성률은 PTMO 및 가소제 함량이 증가할수록 감소하는 경향을 나타내었고, 파단신율은 PTMO 및 가소제 함량이 6 wt%까지는 거의 변화가 없다가 PTMO

Keywords: nylon 6; anionic polymerization; block copolymer; impact stregth; fracture morphology