Plastisol Technology

Fundamentals of the various methods of plastisol technology have been considered in a number of papers, nevertheless the theoretical analysis and the construction of mathematical models have not yet been completed so far. The dipping process has been studied in more detail cf.2 6 10). 

Processability. Plasticizers are often used to increase melt flow during processing, particularly in rubber, ceUulosic plastics, and coatings. In vinyl plastisol technology, powdered resin is slurried in nonsolvent plasticizer at room temperature for easy processing in low-cost equipment and then heated to dissolve and cooled to gel into the final product. 

The more sophisticated products, based on plastisol technology, are quite complex in construction. The requirements for each layer differ significantly, as do their formulations. Thus, clarity and stain resistance are of key importance in the wear layer, whereas foam quality is another major concern in the foam layer. In some sheet flooring products, the backing material is bottom-coated with a PVC layer. 

Flexible vinyl compositions based on plastisol technology and other processing... 

L.H., and Summmerfield, M. (1973) The burning rate flexibility of plastisol DB propellants. Proc. 10th Inti Symposium on Space Technology and Science,... 

For plastisol/organosol technology, high-molecular-weight PVC powder is slurried in liquid plasticizer, and poured, dip- or spread-coated onto metal, fabric, or paper to produce dishwasher racks, upholstery, and wallpaper, respectively. 

Plastisol is a specialized technique for making flexible vinyl products. It is also sometimes called paste or dispersion technology. Basically, powdered PVC is stirred into liquid plasticizer at room temperature to form a viscous liquid or spreadable paste. This can be poured or spread into the shape of the final product, heated to fuse, and cooled to gel into the final solid product. Simple pouring or gentle spreading require no heavy equipment, and do not damage delicate substrates such as... 

The recovery of plasticiser and solvent from waste PVC plastisols, created in the manufacturing process during screen changeovers, has been shown to be possible using ceramic membrane separation technology (152). 

The latexes upon which this industry developed were natural rubber and polychloroprene for solvent resistance. However, technology is advancing to permit penetration of carboxylated nitrile latex for optimized solvent resistance and tougher abrasion resistance. Among the competition to latexes in this field are poly(vinyl chloride) plastisols. As technology develops in producing small particle size latexes from polymers whose synthesis is loo water-sensitive for emulsion polymerization, the dipped goods industry will quickly convert to their utilization from the solvent-based cements of these polymers now employed Prime candidates include butyl rubber, EPDM, hypalon, and vlton. 

The above formulation is cold applied on the surface of adhesive (a rubber layer which has been previously applied to cotton textile). The first dip of PVC plastisol may be followed by the second dip in the same or different plastisol, e g., PVC foam (not given in the patent). If such is the case, the mold with the glove undergoes treatment in a 188-205°C oven for 1-1.5 min after the first layer of PVC was applied, then the complete glove is gelled in the 188-199"C oven for 15-20 min. It is quite apparent that the process is time consuming in this older technology. 

The idea of this invention is to improve resistance to heat and solvents by application of polyurethane system which is not reactive at room temperature but reacts during the gelling process because blocked isocyanate is unblocked at elevated temperature. The plastisol has stable viscosity for 10 days. The plastisol and technology can be used for many different purposes, including dip coating. 

S. Gobstein, "Plastisol and Organisol Technology", in Plastics Additives and Modifiers Handbook, J. Edenbaum, Ed., Van Nostrand Reinhold, New York,... 

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