2020-03-26 16:38:55

fiber nm particle surface fibrils

责任者: WAWKUSCHEWSKI, A;CANTOW, HJ;MAGONOV, SN;HEWES, JD;KOCUR, MA 单位: UNIV FREIBURG,CTR MAT RES,D-79104 FREIBURG,GERMANY.;ALLIED SIGNAL INC,MORRISTOWN,NJ 07962. 来源出处: ACTA POLYMERICA, v 46, APR 1995, p 168- 177 摘要: Surfaces of commercial ultrastrong polymer fibers Spectra(R) 900 and Spectra(R) 1000, which are produced by gel-spinning of ultrahigh molecular weight polyethylene (UHWM PE), were examined with scanning force microscopy (SFM). Measurements were conducted in water in order to minimize surface damage caused by the tip-sample interactions. Different types of imperfections (arbitrarily oriented fibrils, ends of fibrils and discontinuities in surface layers) were found on the fiber surface. These features interfere with the dominating fibrillar structure aligned along the fiber direction. Within the fibrillar structure were found domains of ribbon-like features with a width of 30-110 nm. These ribbons are oriented perpendicular to the fiber direction and were assigned to lamellar platelets overgrown on oriented nanofibrils. SFM images in the nanoscale (1-100 nm) showed that nanofibrils 5-7 nm wide are the elementary construction elements of polymer fibers. They are combined into larger fibrils of 40-50 nm width. Needle-type crystallites 10-30 nm wide were also found on the fiber surface. An extended chain molecular order was detected on surfaces of nanofibrils, needle crystallites, and within the central part of lamellar ribbons. Local regions with long period features having a repeat distance of 15-25 nm were found on the fiber surface. Etching of the fiber surface by elemental fluorination damaged the surface fibrillar structure, and produced deep pores tens of nanometer in diameter in the surface layer. 关键词: MICROPARTICLES; TRANSLOCATION; INTESTINE; MESENTERIC LYMPH NODE; PARTICLE ABSORPTION; PARTICLE QUANTIFICATION PARTICLE ABSORPTION; PARTICLE QUANTIFICATION; MORPHOLOGY; CRYSTALS; POLYMERS