Surface Treatments of Fibers and Effects on Composite Properties

SURFACE TREATMENTS OF FIBERS AND EFFECTS ON COMPOSITE PROPERTIES 

This chapter is concerned primarily with the surface treatments of high performance fibers, including glass, carbon (or graphite), aramid, polyethylene 

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Chapter 5. Surface treatments of fibers and effects on composite properties... 

Effect of size and surface treatment of carbon fibers on mechanical properties of magnesium matrix composites ... 

Polymer composites. The composite research at the Institute is led by Prof. Wu Renjie, Deputy director of the Institute. Chen, et al. (14), studied the effect of oxidation of carbon fiber on the wettability by the binder resin. With the aid of ESCA, they showed that the Q/C ratio on the fiber surface increased with the oxidation time. The interlaminar shear strength also increased correspondingly. Cai Weizhen and her colleagues showed me their exceptional setup for a carbon-fiber composite study. They built their own torsion pendulum for the study of dynamic mechanical properties of the composite and a contact angle goniometer for the study of the composite interface. It was apparent that surface treatment of carbon fiber was their major concern. 

Payae Y, Lopattananon N (2009) Adhesion of pineapple-leaf fiber to epoxy matrix the role of surface treatments. Songklanakarin J Sci Technol 31 189-194 Rahman MM, Khan MA (2007) Surface treatment of coir Cocos nucifera) fibers and its influence on the fibers physico-mechanical properties. Compos Sci Technol 67 2369-2376 Rowell RM, Han JS (2000) Characterization and factors effecting fibre properties. In Frolini E, Leao AL, Mattosso LHC (eds) Natural polymers and agrofibres composites. San Carlos, Brazil, pp 115-127... 

Effects of various chemical treatments such as sodium hydroxide, isocyanate, permanganate, and peroxide on the tensile properties of sisal fiber-reinforced low-density polyethylene (LDPE) composites were investigated. Sodium hydroxide treated fiber composites showed better tensile properties than xmtreated composites, and the enhancement was attributed to their rough surface topography and increased aspect ratio. It was reported that long chain structured cardanol derivative of toluene diisocyanate (CTDIC) treatment reduces the hydrophilic nature of the sisal fiber resulting in improved compatibility and dispersion. It was also reported that peroxide treatment of fiber showed maximum interfacial interactions [33]. 

Different treatments will have different effects on the fiber surface and selection of the best treatment strategy is based on the desired end properties of composites. Effect of some of the treatments on the surface properties of oil palm fibers as reported by various researchers [7, 14, 27, 43, 50-52] are summerized in Table 9.4. Fiber surface properties are most important in the determination of fiber-matrix bonding in composite fabrication. 

In regards to the studies on transcrystalhnity in conventional fiber reinforced composites, their number is vast. A number of issues are related to the formation and growth of TCL [81] crystallinity of the matrix, mismatch of thermal coefficients of the fiber and the matrix, epitaxy between the fiber and the matrix, surface toughness, thermal conductivity, treatment of fiber, etc. Processing conditions such as cooling rate, temperature, and interfacial stress were also found to be important. There are indications that the TC phenomenon is probably too specific for each fiber/matrix system. Nevertheless, it has been recognized that the orientation distribution of the polymer chains in the TCL wUl determine the nature and extent of its effect on the mechanical properties of the composite material [84]. 

Fu Yuan-Fei, Xu Kan, Sun Zhao-Yao, Zhang Fu-Qiang, Chen De-Min, and Li Jing. The effect of silane surface treatment of carbon fiber on the tribological properties of bis-maleimide (BMI) composite. Polym. Plast. Technol. Eng. 51 no. 10 (2012) 1068-1072. 

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