Impact strength filled grades

As with poly(ethylene terephthalate) there is particular interest in glass-fibre-filled grades. As seen from Table 25.8, the glass has a profound effect on such properties as flexural modulus and impact strength whilst creep resistance is also markedly improved. 

Thin wall plastics are used to hot fill (injection and blow molded bottles, thermoformed containers, etc.) without sagging during filling and maintaining mechanical properties such as impact strength and stiffness in temperatures from at least —40°F to 250°F (—40°C to 120°C). Plastic used includes special grades of PEN, PET, PP, PS, and PVC. 

Fabric-Based Grades. Grade Cis made from cotton fabric weighing over 140 g/m2 (4 oz/yd2). The maximum thread count in any ply is 28/cm (72/in.) in the fill direction, and the maximum total thread count in the warp and fill directions is 56/cm (140/in.). Heavier fabrics provide higher impact strength but rougher machined edges. Its use for electrical applications is not recommended. 

Since the early discovery of miscibility between the low-cost polystyrene and PPE, several commercial grades of PPE/HIPS have been developed, which offer a wide choice of heat resistance (DTUL), impact strength, and melt processability (Cizek 1969 Fried et al. 1978). This versatility of PPE/HIPS blends led to their unparalleled commercial success, accounting for nearly 50 % of market volume of all engineering polymers commercial blends. PPE/HIPS blends filled the price-performance gap between the styrenic resins (HIPS, ABS) and the engineering resins such as polycarbonate, polyarylate, and polysulfones. The technology of PPE/HIPS blends has already been discussed previously under the styrenic blends section (Sect. 19.3), and the typical blend properties are shown in Tables 19.6 and 19.32. 

The most commonly used plastic for inserts is polyamide 6,6. This is used in both natural and glass-filled forms. A wide variety of grades are available but care must be exercised in their selection. Properties of modulus, impact strength and heat resistance should be optimised in the selection process. In production it is nsefni to monitor the filler content and type together with the glass transition temperatnre. 

The size of the crushed ore can be further reduced using roller mills or cone crushers. The requirements of the talc-plastic composite determine the fineness of the talc. A standard grinder roller produces 50 pm particles, finer grades are between 10 and 40pm, and the finest grades are between 3 and 10 pm [2]. Roller-milled products are used in low impact strength polymer-filled parts, such as fans in automotive under-the-hood applications. Fine micronization (1-12 pm) is carried... 

Several grades of PPO are available that have been developed to provide a choice of performance characteristics to meet a wide range of engineering application requirements. Glass-filled phenylene oxides provide up to double the mechanical strength, four times the modulus, and improved impact strength from —46 to 121°C. 

Description Aminosilane surface-treated grades, giving improvements in physical properties compared with untreated fillers, esp. low warpage, high impact strength specially developed for mineral-filled polyamides can also be used in polyesters, urethane, PVC and other thermoplastics white colour ... 

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