Preparation of Polymer Composites

If the oil phase is replaced in an oil in water (o/w) emulsion by a hydrophobic monomer, or the water phase in a water in oil (w/o) emulsion by a hydrophilic monomer, an emulsion is obtained that can be employed as a precursor for the preparation of polymer latexes [10, 11]. Similarly, if both phases are replaced, the oil phase by a hydrophobic phase containing a monomer and the water phase by a hydrophilic phase containing a monomer, the generated emulsion could be employed as a precursor in the preparation of polymer composites [12]. However, concentrated emulsions that are generated and stable at room temperature may become unstable at the polymerization temperature. To be suitable for the preparation of polymers and polymer composites, the concentrated emulsion must first form and, subsequently, it must remain stable at the temperature at which polymerization takes place. The scope of the present section is to investigate the factors that influence the formation and stability of concentrated emulsions at the preparation and polymerization temperatures in order to identify the physico-chemical conditions that ensure their stability [9],... 

Table 13. Representative compositions in the preparation of polymer composites polystyrene particles dispersed in cross-linked polyacrylamide...

Another approach to improve the properties of chitosan hydrogels is via the preparation of polymer composites. Porous hydrogels of N-carboxymethyl chitosan/polyvinyl alcohol were prepared by Lee et al. [99]. Hydroxypropyl chitosan was combined with sodium alginate for the formation of biodegradable hydrogels [100]. Chitosan-hyaluronic acid composite was prepared by Tan et al. [101]. 

Non-covalent functionalisation approaches also enable the preparation of polymer composites with significantly improved mechanical properties. For example, in the recent work of Yuan et al three different polymers such as polyimide without side-chain (PI), polyimide-graft-glyceryl 4-nonylphenyl... 

Key words vegetable oil-based polymer composites, preparation of polymer composites, properties of polymer composites, appUcation of polymer composites. 

Figure 1.1 (b) Types of fiber reinforcement used in the preparation of polymer composites 11,15,16]. 

For the preparation of polymer composites, generally two types of fibers, namely synthetic and natural fibers, are used as reinforcement. Figure 1.1(b) shows different types of natural/synthetic fibers frequently used as reinforcement in the polymer matrix composites. 

For the preparation of polymer composites, xmsaturated polyester resin was reinforced with raw and surface-modified particle (90 microns) fibers in four different proportions... 

This is a common technique for the preparation of polymer composites. In the first step, dispersion of filler is achieved in appropriate solvent through mechanical stirring or sonication, followed by dissolution of the polymer in the same solvent. The dispersed fillers are then mixed with polymer solution either at room temperature or at higher temperature depending on the solubility of the polymer. Composite films are obtained either by precipitation or by casting the solution/mixture. 

Scheme 2.4 NBE/MMA microemulsion using ROMP and ATRP in aqueous heterogeneous systems for the preparation of polymer composite nanoparticles. Reproduced with permission of J. Polym. Sci.

Nut HP, Hossaiii MA, Sultana S, Mollah MM. Preparation of polymer composites using natural fiber and their physic-mechanical properties. Bangladesh J Sci Ind Res 2010 45 117-122. 

FIGURE 11.1 Thermal conductivity of typical polymer matrices used in preparation of polymer composites. (Adapted from Tong Xingcun Colin. Advanced materials for thermal management of electronics packaging. New York Springer, 2011.)... 

Bream, C.E., Hinrichsen, E., Hornsby, P.R., Tarverdi, K.T. and Williams, K.S. Integrated compounding technology for the preparation of polymer composites containing waste materials Paper presented at the July PPE Conference, Bradford University, U.K, 1997. 

A development of methods for preparation of polymer composites containing inorganic NPs is one of the hottest topics in nanoscience because of the unique electrophysical behavior, antibacterial and catalytic activity of such composites. During recent years, attention has been focused on elaboration of a simple single-stage method for production of polymer-metal hybrid materials directly in swollen polymer matrices via a reduction of metal ions incorporated into hydrogels [110-112] or bound to polyelectrolytes [81-85, 103-105, 113-117]. 

Polysilanes react readily with surfaces and molecules containing nucleophilic oxygen. Thus, they can be used as adhesion promoters on glass or oxide materials. The preparation of polymer composites reinforced by glass particles is one example of... 

Fig. 31. Integrated twin-screw extrusion compounding technology for the preparation of polymer composites filled with fibrous recyclate additives...

Preparation of Polymer-Composites Containing Both p- and n-Type Nanoparticles... 

NEW APPROACHES FOR PREPARATION OF POLYMER-COMPOSITE FILMS AND FIBERS... 

The addition of functionalized polymers offers the advantage to achieve the blend compatibUization (emulsifying effect) by using a smaU amount (a few percent) of modified component. This method has found large application, especially for blending of polyolefins with polar polymers, such as polyamides, polyesters, polyethers moreover, it can be useful in the preparation of polymer composites with various types of fillers [96]. 

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