Coating scratch-resistant

A more recent development of interest with this material is that scratch-resistant coatings may be stoved on at temperatures not feasible with conventional bisphenol A polycarbonates to give products with a scratch resistance comparable to glass. 

The polymerization reaction (Equation 5) leads to materials with extremely hard surfaces. Based on this, a new type of scratch resistant coating for different purposes could be developed. Table I gives some data of the high scratch resistant coating developed for CR 39 plastic eye glass lenses (39). 

In principle these compounds offer access to materials with AliCh-SiCL and Al203 2Si02 stoichiometries. The latter stoichiometry is equivalent to the Al[OSi(OBu-t)3 (OBu-t)] precursor. The major drawbacks with these materials are their air and moisture sensitivity, and the cost of the starting materials. Although the idealized stoichiometries of the above ceramics products are not those of crystalline aluminosilicates, amorphous aluminosilicate glasses are often important in optical applications or in scratch-resistant coatings. Furthermore, they may offer potential for CVD-type applications. There still remains considerable need for simple precursors to crystalline aluminosilicates, especially for structural applications. Dense, phase pure crystalline ceramic materials are desired for optimal mechanical properties, e.g. ceramic fibers for composite manufacture. 

Recent advances in polycarbonates include further enhancement of normally good fire resistance color elimination (an improvement approaching glass) and development of scratch-resistant coatings for glazing applications branched material for blow-molding bottles optimization of structural foam molding and compounds selective copolymerization and development of many different commercial polyblends. 

Hydroxyl-containing fluoropolymers made of fluoroolefin and hydroxyalkyl vinyl ether, hexamethoxymethylmelamine, and silica form highly cross-linkable liquid mixtures and can be applied as an excellent scratch-resistant coating on plastic objects [2.27], [2.28]. 

Ultra-high molecular weight polyethylene (UHMWPE) can also be considered as sncb an intentional additive, becanse it can be nsed for scratch-resistant coatings, which can... 

Energy, catalytic, and structural applications account for the remaining 12%. Uses include catalyst supports (e.g., for low-temperature H2 production), ceramic membranes, fuel cells, and scratch-resistant coatings. 

Multilayer ceramic capacitors Orthopedics Scratch-resistant coatings... 

Uses Urethane-acrylic, cure accelerator, gloss aid for wood coatings, fillers, lithographic inks, scratch resist, coatings on plastics Features Provides very fast cure with exc. hardness and solv. resist. Properties Gardner 2 color m.w. 1000 vise. 28,000 cps tens. str. 8000 psi tens, elong. 3%... 

Chem. Descrip. Multifunctional polyester acrylate Uses Polyester-acrylic in coatings for paper, wood and plastics, scratch resist, coatings, paper upgrading Features Fast cure, hardness, and solv. resist. 

Staudigl G, Benien H, Suchentrunk R (2000) Transparent scratch resistant coatings on plastics. Materialwiss Werkstofftech 31 360-364... 

Silica-Filled UV-Cured Acrylates for Scratch-Resistant Coatings... 

Pyrogenic silica is normally used in amounts smaller than 1 wt% in order to control the resin rheological behavior. However, for scratch-resistant coating systems the... 

Low molecular weight polysilicic acid is combined with tetrafluoroethylene-vinyl acetate copolymer to give a hard scratch-resistant coating on clear plastic shee (186). Additional compositions involving polysilicic acid with other polymers a. tetrafluoroethylene copolymers were also developed (187). 

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