A Study of Bi-Axial Stretching Process for the PTFE Membrane(I)

이축연신 PTFE 막 제조 공정에 관한 연구(I)

  • Published : 2007.06.30

Abstract

A few of polytetrafluoroethylene(PTFE) membranes and PTFE fine powders were analyzed to chooce an optimum resin. The bi-axial stretching process was developed to set up the foundation of the preparation process and control the pore size and porosity of PTFE membrane. The pretreatment of PTFE fine powder used in the preparation process for PTFE was needed. The mixing of additives, the ripening of mixture, paste extrusion process of ripening powder, calendering process and the bi-axial process were conducted for controlling pore size, porosity and thckness of membrane. The aftertreatment which strengthened the mechanical properties was necessary. The control of pore size and porosity of the membrane were determined. The ratio of PTFE fine powder and additives at the paste extrusion process, the ripening time, the ripening temperature and the parameters of temperature and pressure at the paste extrusion process were optimized.

이축 연신에 의한 폴리테트라플루오르에틸렌(PTFE) 막을 제조하기 위한 공정 조건을 확립하기 위하여 상용화되는 PTFE 막 및 PTFE 미세 분말을 선택하였다. 막 제조공정에 사용 되기 위해 PTFE 미세 분말은 전처리 되었고, 첨가제와 혼합되었으며, 혼합물의 숙성, 페이스트 압출 공정, 칼렌더 가공 공정 등이 수행되었고 막의 두께 및 기공크기와 다공성을 측정하였다. 기계적 물성을 강화하기 위하여 시료의 후처리가 실시되었고, PTFE 막 제조공정을 위한 페이스트 압출 공정에서의 PTFE 분말과 첨가제의 혼합비, 숙성 시간, 숙성 온도, 압력 등에 관한 공정 조건이 확립되었고, 기공크기(pore size)와 다공성(porosity)을 조절할 수 있는 이축연신 공정에 대한 최적공정 조건도 확립하였다.

Keywords

References

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