High-performance plastics

Acetal Resins. These are high performance plastics produced from formaldehyde that are used for automotive parts, in building products, and in consumer goods. Acetal resins (qv) are either homopolymers or copolymers of formaldehyde. Typically, the resin is produced from anhydrous formaldehyde or trioxane. The acetal resins formaldehyde demand are 9% of production (115). 

The aromatic sulfone polymers are a group of high performance plastics, many of which have relatively closely related stmctures and similar properties (see Polymers containing sulfur, polysulfones). Chemically, all are polyethersulfones, ie, they have both aryl ether (ArOAr) and aryl sulfone (ArS02Ar) linkages in the polymer backbone. The simplest polyethersulfone (5) consists of aromatic rings linked alternately by ether and sulfone groups. 

In 1990 the majority of U.S. PCB production resulted from subtractive or print-and-etch processing additive processes were less than 6% of the total multilayer boards accounted for 55.8%. The ratio of rigid to flexible surface areas plated is about 15 1. High performance plastics including polyimide. Teflon, and modified epoxy comprised 6% of the market ( 324 million) flexible circuits were 6.6% ( 360 million) (42). 

These materials also have high thermal and oxidative stabiHty. Flexible segments such as amide siloxane can be incorporated into the imide-based stmcture for hot melt or injection appHcations. General Electric (GE) and Hoechst-Celanese are suppHers of these high performance plastics. 

The pace of development has increased with the commercialization of more engineering plastics and high performance plastics that were developed for load-bearing applications, functional products, and products with tailored property distributions. Polycarbonate compact discs, for example, are molded into a very simple shape, but upon characterization reveal a distribution of highly complex optical properties requiring extremely tight dimension and tolerance controls (3,223). 

Bao, Z. Feng, Y. Dodabalapur, A. Raju, V. Lovinger, A. 1997. High-performance plastic transistors fabricated by printing techniques. Chem. Mater. 

Jackson, Jr, W. J. and Morris, J. C., Poly esters of 4,4 -biphenyl dicarboxylic acid and aliphatic glycols for high-performance plastics, in Liquid Crystalline Polymers, ACS Symposium Series, Vol. 453, American Chemical Society, Washington, DC, 1990, pp. 16-32. 

Timar, M.C., Maher, K., Irle, M. and Mihai, M.D. (2004). Thermal forming of chemically modified wood to make high performance plastic-hke wood composites. Holzforschung, 58(5), 519-528. 

Plastics and polymer composites are much more expensive than metals, even more-specialized ones such as nickel. As for the specific mechanical properties, the high densities of metals modify the classification of the various materials. According to the cost per volume, plastics are competitive. Only the very high performance plastics or composites are more expensive than metals. 

The dynamic seals for reciprocating plungers and pistons, as well as rotating shafts, require all the capabilities of modem material developments high performance plastics, bronzes,... 

S. Angiolini, M. Avidano, R. Bkacco, C. Barlocco, N.G. Young, M. Trainor and X.-M. Zhao, High performance plastic substrates for active matrix flexible FPD, Society For Information Display, Digest of Technical papers, 2003, 1325—1327. 

The RDX-NG-NC pellet is a high performance plastic explosive composed of 60% RDX and 40% ND added to 3% NC with an explosion speed of 7,800 m/s in a PVC pipe with a 30mm inner diameter. The same dimensions as the RDS pellet were added to it The detonator used was the electric detonator No. 6 made by Nippon Oil Fats. The test was carried out in the explosion test shelter in TaketoyoWorks of Nippon Oils... 

These PPA heat resistant, high performance plastics have been used successful in different applications such the auto engine block. BP Amoco reports that after seven years and 85,000 miles of actual vehicle use, a Dodge Neon 2.0 liter thermostat housing molded from BP s PPA (polyphthalamide) showed no measurable dimensional variations, no surface degradation, and no decline in the performance of the plastic. In 1994, BP model A-113 3 HS (a 33wt% glass-filled, heat-... 

PID Controller Saves Space, Yet Maintains High Performance, Plastics Auxiliaries Machinery, Jan/Feb. 2002. 

Dow Chemical also pioneered the shape-selective dialkylation of polyaromatics, e.g. naphthalene and biphenyl (see Fig. 2.12), using the same type of 3-DDM catalyst [39]. The products are raw materials for the production of the corresponding dicarboxylic acids, which are important industrial monomers for a variety of high performance plastics and fibres. 

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