Properties of polymers reinforced with

The properties of polymers reinforced with chopped glass fibres dispersed in the polymer matrix depend on ... 

The focus of this review is the properties of polymers reinforced with silica, however, the synthetic approaches of incorporating silica into polymers will also be briefly discussed. 

The mechanical properties of composites reinforced with wood fibers and PVC or PS as resin can be improved by an isocyanate treatment of those cellulose fibers [41,50] or the polymer matrix [50]. Polymethylene-polyphenyl-isocianate (PMPPIC) in pure state or solution in plasticizer can be used. PMPPIC is chemically linked to the cellulose matrix through strong covalent bonds (Fig. 8). 

The investigations mentioned above, are focused principally on the processing and mechanical response of polymers reinforced with natural fibers, without considering that their mechanical properties decrease after exposition to alkaline environmental of cement materials or weather. Natural fibers reduce their mechanical properties after exposition to alkaline environment of the cement matrix, nevertheless the use of polymeric matrix as a binder aroimd the natural fibers provides protection for them. However, if the interface of composites is not good, and/or matrix is not alkaline resistant, hydration products like calcium hydroxide will migrate to interface, and polymer composite will deteriorate. Several studies have demonstrated that the mechanical properties of natural fibers decrease after exposure to alkaline environment of the cement matrix due to three different mechanisms [30-39] ... 

Y. Zhang, J.E. Mark, Y. Zhu, R.S. Ruoff, D.W. Schaefer, Mechanical properties of polybutadiene reinforced with octadecylamine modified graphene oxide. Polymer, ISSN 0032-3861 55 (21) (October 9, 2014) 5389-5395. http //dx.doi.0rg/lO.lOl6/j. polymer.2014.08.065. 

Some engineering applications of polymers reinforced with glass fibre and carbon fibres are shown in Tables 2.4 and 2.5. It is seen that there are wide ranges of applications particularly in glass fibre, carbon fibre and nanotubes. Many of these applications require polymers, which have a particularly high standard of properties, for example, stability in impact and tensile properties, thermal properties, dimensional stability and, chemical and oil resistance. 

The concept of polymer reinforcement by monomolecular fibres is already old but many studies date from the last decade. The interest is particularly the very high aspect ratios and the levels of reinforcement with expected mechanical properties as high as ... 

Table 5.1. Carbon nanotubes have a high potential to improve the mechanical, physical and electrical properties of polymers, as stated by Thostenson et al. (4). They exhibit an exceptionally high aspect ratio in combination with low density, as well as high strength and stiffness (Coleman et al. (5)), which make them a potential candidate for the reinforcement of polymeric materials.

The performance expected from a sealant and the polymer used in its production determine the type of fillers used. From the point of view of performance, sealants can be divided into these having plastic behavior and these with elastomeric behavior. Sealants which have plastic behavior are low-cost and low-performance products which are being gradually eliminated from the market. These sealants use inexpensive fillers to lower cost and regulate non-sag properties. Typical fillers used in these products are calcium carbonate and some fibrous materials which are used as replacement for asbestos which was very popular in the past. This combination of fibrous and spherical particles provided a useful tool to the sealant formula-tor to regulate non-sag properties which are very important in sealants. Fibers have also been used to reinforce these products because the properties of polymers were poor. 

Solid additives in the shape of spheres, cubes, or platelets generally act as a filler (extender) and, with the exception of raising stiffness, do not Improve the mechanical properties of the composite. With very strong adhesive forces between filler surface and polymer chains, however, a filler may also provide reinforcement, for example, carbon black in rubber or uncoated calcium carbonate in polyamides. 

The above mentioned scaffolds were made completely of the ceramic materials. Other potential materials which could be used to fabricate a novel construct for the repair of ciitical-sized bone defects is a novel material made of biodegradable polymer reinforced with ceramics particles. The properties of such a composite depend on 1) properties of the polymer used for the matrix and properties of the ceramics used for the reinforcement, 2) composition of the composite (i.e. content of ceramic particles) and 3) size, shape and arrangement of the particles in the matrix. Several polymer-composite composites have been used for scaffolds fabrication including polylactide (PLA) and polycaprolacton (PCL) reinforced with calcium phosphate (CaP) micro and nanoparticles. Authors proposed a novel composite material by blending copolymer -Poly(L-lactide-co-D,E-lactide) (PLDLLA) a copolymer with a ceramic - Tri-Calcium Phosphate... 

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