Blends of new thermotropic liquid crystalline polymer(TLCP) having alkoxy slde-groups with poly(butylene terephthalate)(PBT) were prepared by the coprecipitation from a common solvent. The blends (1%, 3%, 5%, 7%, and 10% LCP/PBT) were processed for fiber spinning to examine their tensile properties in the various draw ratios. The fibers were extruded through a capillary die at 245℃ to produce a monofilament. In 5%, 7%, and 10% LCP/PBT blends, LCP domains were very well dispersed and showed fibrillar structures. The morphology of 5% LCP/PBT blend was revealed fibrillar LCP domains with 60∼70nm in diameter which were fine dispersed in the PBT continuous phase. The maximum values of the ultimate strength were obtained from the blend containing 5% of the LCP at any draw ratios. Thermal, morphological and mechanical properties of the blends were examined by DSC, optical microscopy, SEM and capillary rheometry.
알콕시 곁사슬을 가지는 열방성 액정고분자(TLCP)를 합성하고, 합성된 TLCP와 PBT를 혼합용매중에서 블렌딩 하였다. 블렌드물을 섬유형태로 방사하여 LCP의 농도를 1%, 3%, 5%, 7% 그리고 10%로 변화시켜 연신비조건에 따른 인장강도와 초기 모듈러스 값을 측정하였다. 섬유방사는 245℃에서 행하였다. LCP 농토가 5% 일때 최대 인장강도 값을 얻었으나, 그 이상의 LGP 농도에서는 오히려 감소하였다. 이때 전자현미경을 이용하여 지름이 약 60∼70nm의 고른 섬유형태의 LCP가 매트릭스 PBT에 분산됨을 확인하였다 그러나 초기 모듈러스는 블렌드의 LCP 농도가 증가함에 따라 꾸준히 증가하였다.
Keywords: side-group thermotropic LCP; blending; spinning; mophology