Fibers environmental effects

The moisture sensibility is remarkable, certain natural fibers can easily be influenced by environmental effects. Generally speaking, the mechanical properties are lowered with rising moisture content. 

The mechanical properties of composites are mainly influenced by the adhesion between matrix and fibers of the composite. As it is known from glass fibers, the adhesion properties could be changed by pretreatments of fibers. So special process, chemical and physical modification methods were developed. Moisture repel-lency, resistance to environmental effects, and, not at least, the mechanical properties are improved by these treatments. Various applications for natural fibers as reinforcement in plastics are encouraged. 

A number of areas in which plastics are used in electrical and electronic design have been covered there are many more. Examples include fiber optics, computer hardware and software, radomes for radar transmitters, sound transmitters, and appliances. Reviewed were the basic use and behavior for plastics as an insulator or as a dielectric material and applying design parameters. The effect of field intensity, frequency, environmental effects, temperature, and time were reviewed as part of the design process. Several special applications for plastics based on intrinsic properties of plastics materials were also reviewed. 

Environmental effects on composite strength can be apparent in shortterm tests at high temperatures. For example, Prewo et al. observed pronounced differences in the stress-strain response of continuous fiber/glass-... 

The size and shape of hair fibers also vary along the fiber length, providing a plus for the averaging techniques for determining fiber cross-sectional dimensions. These variations have been attributed to growth patterns as well as to environmental effects [107]. 

Gopalan, R., Somashekar, B.R., and Dattaguru, B. 1989. Environmental effects on fiber-polymer composites, Polym. Degradat. Stabil, 24,361-371. 

Yun, H.M., J.C. Goldsby, and J.A. DiCarlo. 1995a Environmental effects on tensile creep and stress rupture properties of advanced SiC fibers. Pp. 331-336 in High-Temperature Ceramic-Matrix Composites 11 Manufacturing and Materials Development Vol. 58 in Ceramic Transactions, A.G. Evans and R. Naslain (eds.). Westerville, Ohio American Ceramic Society. 

M. Robert, R. Roy, B. Benmokrane, Environmental effects on glass fiber reinforced polypropylene thermoplastic composite laminate for structural applications. Polym. Compos. 31, 604-611 (2010)... 

Optical sensors offer some advantages over electrochemical methods [10, 11]. First, no reference electrode is required however, reference intensity is necessary to minimize environmental effects on the system. Second, fiber-optic sensors... 

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