Polyvinyl chloride plastisol

P.V.C. plastisols P.V.C. plastisols are liquids which contain little or no solvent/diluent. They consist of a blend of polyvinyl chloride (p.v.c.) resins, plasticisers, stabilisers, viscosity depressants, pigments and sometimes fillers. 

Gravimetric hoppers feed a mold with a prescribed weight of polymer. The feed stock is either a finely divided powder or a liquid plastisol. A plastisol is a suspension of a resin powder, typically polyvinyl chloride, in a plasticizer, used to manufacture. Rotational molders use liquids and powders in their process since both flow freely. This property permits the easy addition of the materials to the mold. More importantly, they flow smoothly around the interior of the mold as it rotates. In doing so, they coat the entire surface. 

Many polymers can be purchased as finely divided powders. These include polyethylene, polycarbonate, nylon, and rigid or lightly plasticized polyvinyl chloride. Highly plasticized polyvinyl chloride comes in a plastisol form. After the material is charged into the mold it is clamped shut prior to heating and rotation. 

Polyvinyl chloride is also widely used. Rigid polyvinyl chloride is introduced to the mold in powder form. The material is chosen for durable constructions because of its chemical resistance and ease of processing. It incorporates functional additives and demolds easily. Plasticized polyvinyl chloride can be used to produce flexible parts such as balls and soft toy parts. The polyvinyl chloride is introduced to the mold as either a plastisol or powder. A plastisol is a suspension of granules in a plasticizing agent. When heated, the polymer granules absorb the plasticizer and fuse to form a cohesive, flexible material. 

The plasticizer-range alcohols are largely used as feedstock for production of high molecular weight diesters of phthalic, adipic, azelaic, and sulftiric acids. All these are used primarily in plasticizers for polyvinyl chloride (PVC) and other plastics. The plastics industry also uses them as additives for heat stabilization, to control the viscosity of PVC plastisols, ultraviolet absorbers, flame retardants, and antioxidants. They are also found in synthetic, lubricants, agricultural chemicals, and defoamers. 

Uses. Plasticizer in polyvinyl chloride films, sheeting, extrusions, and plastisols solvent and emollient in cosmetics... 

Another very important property of plasticizers for PVC resins is the ability to act as a dispersing medium for polyvinyl chloride plastisols. The performance of the particular plasticizer in a plastisol application depends to a great extent on a property known as its viscosity stability. The stability of the plastisol to viscosity build up is the manifestation of the solvating effects of the plasticizer, and thus, those materials with higher solvating efficiency tend to display an increase in plastisol viscosity on standing. Figure 3 is the plot of the viscosity stability of PVC o-phthalate ester plastisol compositions and, in essence, compares the alcohol-derived plasticizers with that of the olefin-derived plasticizer. The data show that... 

Other Plasticizers. Acetyl tributyl citrate is an outstanding nontoxic plasticizer for polyvinyl chloride in food packaging Plastisol formulations containing this ester have exceptional viscosity stability. Acetyl triethyl citrate is a good plasticizer for the cellulosics and acetyl trioctyl citrate shows promise with vmylidene chloride polymers. Other compounds of diverse nature find application as plasticizers. These include tetra-w-butyl thiodisuceinate, camphor, o-nitrobiphenyl and partially hydrogenated isomeric terphenyls... 

Plastisols are used for molding thermoplastic resins, chiefly polyvinyl chloride. See also Plasticizers. 

The formation of coagulum is observed in all types of emulsion polymers (i) synthetic rubber latexes such as butadiene-styrene, acrylonitrile-butadiene, and butadiene-styrene-vinyl pyridine copolymers as well as polybutadiene, polychloroprene, and polyisoprene (ii) coatings latexes such as styrene-butadiene, acrylate ester, vinyl acetate, vinyl chloride, and ethylene copolymers (iii) plastisol resins such as polyvinyl chloride (iv) specialty latexes such as polyethylene, polytetrafluoroethylene, and other fluorinated polymers (v) inverse latexes of polyacrylamide and other water-soluble polymers prepared by inverse emulsion polymerization. There are no major latex classes produced by emulsion polymerization that are completely free of coagulum formation during or after polymerization. 

Effect of Spray Drying Parameters on Polyvinyl Chloride Resin Particle Size Distribution and Plastisol Rheology... 

As the shear rate increases, the viscosity of some dispersions actually increases. This is called dilatancy, or shear-thickening. Dilatancy can be due to the dense packing of particles in very concentrated dispersions for which at low shear, the particles can just move past each other but at high shear they become wedged together such that the fluid cannot fill (lubricate) the increased void volume, and the viscosity increases. An example of this effect is the apparent drying of wet beach sand when walked on, the sand in the footprint initially appears very dry and then moistens a few seconds later. Other examples include concentrated suspensions (plastisols) of polyvinyl chloride (PVC) particles in plasticizer liquid and the commercial novelty product Silly Putty (which is a silicone material). 

Thermal degradation and degradation kinetics of polyvinyl chloride (PVC) plastisols, plasticised by polymeric plasticiser, were examined using dynamic and... 

Brighton, 20th-22nd April 1999, p.249-57 IMPROVED PLASTISOL FLOW AND REDUCED LEVEL OF PLASTICISER IN PASTE POLYVINYL CHLORIDE FORMULATIONS Saethre B Thorjussen T Jacobsen H Pedersen S Leth-Olsen K-A Hydro Polymers AS (IOM Communications Ltd. BPF)... 

Butyl benzyl phthalate is a plasticizer added to polymers to give flexibility and softness. It is used extensively in polyvinyl chloride and in cellulose plastics, polyvinyl acetate, polysulfides, and polyurethane. Also used in flexographic inks for food packaging applications and acrylic coatings, profile extrusions, slush moulding, film and sheeting, coated fabrics, floor and wall coverings, vinyl foams and plastisols for car sealants. 

Plastisol Adhesive consisting of polymers (e.g., polyvinyl chloride) in plasticizers, solidifying to an adhesive or sealing layer by (physical) entrapment of the polymer in the plasticizers when heated (sol-gel transformation). 

Recently, so-called plastisol fabricating techniques have been developed which allow the cheap and efficient manufacture of many articles from polyvinyl chloride. Plastisds ere dispersions of pdyvinyl chloride in appropriate solvent mixtures or in plasticizers. Molds are either coated by... 

The starting material in these process is not necessarily in the liquid state also polyvinyl chloride (PVC) pastes (plastisols) can be used, as well as even a well-flowing thermoplastic powder [17]. The particles will melt when in contact with the heated wall and will form a compact layer of material. The softened powder sticks to the wall, and other particles gradually complete the shaping process. Only the outer surface of an article made this way will be smooth, which is not objectionable for many applications. 

A polyvinyl chloride plastisol is a dispersion of very fine particle size polyvinyl chloride in a plasticizer. 

Polyvinyl Chloride. In plastisol processing, PVC is dispersed in hquid plasticizer then fused to a sol and cooled to a gel to produce rubbery products. When the processor wants to decrease the plastisol viscosity without excessive softening of the final product, he uses a polymerizable plasticizer such as a glycol diacrylate (Fig. 3.71) plus a little peroxide. The plasticizer gives a more fluid plastisol, and then, during hot fusion, the peroxide crosslinks the plasticizer to prevent excessive plasticization of the finished product. 

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