Paste resin

Any one of several commercially available PVC paste resins may be used. [Exon 654 (Firestone) and QYNV (Union Carbide) are used in the formulations given in Table I Geon 121 (Goodrich) has also been used (17, 19).] The various resins may not yield identical values for some of the propellant properties such as fluidity of uncured propellant, and the physical properties and thermal stability of the cured propellant,... 

Pigments are available in a number of commercial forms including dry powders (either surface treated or untreated), presscakes, flushed colors (thick pastes), fluidized dispersions (pourable pastes), resin predispersed pigments (powders), and plastic color concentrates or master batches (granules) (see Pigment dispersions). 

The manufacture of wallcoverings has become an important outlet for paste resin—some 80000 tonnes in Western Europe in 1989, or 14.5% of the total demand for resin of this type. 

In some formulations filler or extender resin can be used—partly for economy and partly to reduce the viscosity (especially for harder products, with low plasticizer contents). Often, however, the particle sizes of such additives are of the order of 35 pm, much larger than are the particles of the paste resins (5 to 20 pm), and because of this they cannot be used in formulations for thin coatings—that is, of weights less than 200 gm J. 

Residual materials (e.g., surfactants, emulsifiers) from polymerization which remain on the surface of the resin particle can exhibit unique secondary manifestations of degradation, such as poor heat and light stability and susceptibility to fungal attack not associated with the polymer itself. This is particularly true of emulsion-prepared polymers (dispersion or paste resins) where the surfactant level may be as high as 3% to provide appropriate rheological properties to the resin. 

There are many types of color concentrates (also called masterbatches) to choose from, including liquid, paste, resinated blends, so-called freeze dried, universal concentrate, resin specific, and encapsulated. All types have strengths and weaknesses that have to be considered when choosing what is right for an application. This chapter will attempt to clarify some of those differences. The liquid and paste types, however, will be left to another chapter since they are somewhat different from the rest, in both how they are made and how they are used. 

When E-PVC resins are mixed with a liquid plasticiser, a paste (or plastisol) is produced. Consequently these resins are called paste resins. They are used in a wide range of speciality applications such as coating, dipping or spreading. 

Phenolics Phenol and resorcinol formaldehyde adhesives cure by condensation polymerisation with the elimination of water, and therefore require high curing pressures. They are normally available as two-component systems consisting of a paste resin and a liquid hardener. Traditional uses include wood bonding and plywood fabrication, but nowadays phenolics, especially modified phenolics, are also used in structural bonding of metals and plastics. 

Paste resin A term sometimes used for PVC resins used in making vinyl dispersions such as plastisols. 

Stir-in resin (dispersion resin, paste resin) n. A vinyl resin that does not require grinding or extremely high-shear mixing to effect dispersion in a plasticizer or to form a plastisol or organosols. 

Plasticizers can also function as vehicles for plastisols and organosols (see paste resins) and as carriers for pigments and other additives. Some plasticizers offer heat and light stabilization as well as flame retardance. 

In-house tests have been collected and correlated by national and international standards organizations to make them universally applicable. ISO has defined tests and standards set up by other organizations such as the ASTM and DIN so that ISO methods are now widely accepted worldwide. ASTM D1755 defines a system for classifying general-purpose (mass and suspension) and dispersion (paste) resins (55). 

Comf ehensive Index AdhesNe Pastes Resins... 

Wallpaper paste resins Methyl, ethyl, etc. vinyl... 

Shenyang Chemical Industries Group has 4000+ employees. Major products include PVC paste resin with annual capacity of 28 000 tonnes. The company has received approval from China s State Development and Reform Commission for its two chemical projects, to invest 4.0 billion yuan (US 480 million), for the production of ethylene, PVC and acrylic acid. Construction was due to start in 2004 and will be completed in 2006. 

Built in 1959, the Zhejiang Juhua Electric Chemical Plant is the largest chloro-alkali production enterprise in Zhejiang Province with annual capacity of 120 000 tonnes of caustic soda. The company has 25 000 employees and produces PVC paste resin with annual capacity of 35 000 tonnes. Other primary products are hydrochloric acid, liquid chlorine, chlorobenzene bleaching powder and ADC vesicant. 

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