Chlorinated light stability

The process of post-chlorinating PVC was carried out during World War II in order to obtain polymers soluble in low-cost solvents and which could therefore be used for fibres and lacquers. The derivate was generally prepared by passing chlorine through a solution of PVC in tetrachloroethane at between 50°C and 100°C. Solvents for the product included methylene dichloride, butyl acetate and acetone. These materials were of limited value because of their poor colour, poor light stability, shock brittleness and comparatively low softening point. 

Light Stability of Chlorinated Dibenzo-l -dioxins. A known concentration of chlorinated dibenzo-p-dioxin was placed in a quartz 1-cm path length cell. A General Electric R.S. sunlamp was placed either 0.5 or 1.0 meters from the face of the cell. The stability of the chlorinated dibenzo-p-dioxin was monitored using ultraviolet spectroscopy. 

The variety of substances used as additives in polymers is considerable. For example, the fillers may include china clay, various forms of calcium carbonate, talc, silicas (diatomaceous silica), silicates, carbon black, etc. The impact modifiers typically include other polymers. Plasticizers include certain polymers with low (oligomers), dialkyl phthalates, dialkyl sebacates, chlorinated paraffin waxes, liquid paraffinic fractions, oil extracts, etc. Heat stabilizers include heavy metals salts such as basic lead carbonate, basic lead sulfate, dibasic lead phosphite (also acting as a light stabilizer), dibasic lead phthalate, stearates, ricinoleates, palmitates and octanoates of cadmium and barium, epoxide resins and oils, amines, diphenylurea, 2-phenylindole, aminocrotonates. The antioxidants include tris-nonyl phenyl phosphite, 2,6-di-ferf-butyl-p-cresol (BHT), octadecyl-3,5-di-terf-butyl-4-hydroxyhydrocinnamate, etc. The UV stabilizers include modified benzophenones and benzotriazoles. Processing lubricants include calcium stearate, stearic acid, lead stearate, various wax derivatives, glyceryl esters and long-chain acids. Fire retardants include antimony oxide, some pyrophosphates, etc. 

Use Heat and light stabilizer for vinyl plastics and chlorinated paraffins. As an UV screening and antioxidizing stabilizer for vinyl and other chlorinated resins in paints and plastics. 

Chelex MD Diphenyl isodecyl phosphite DPDP EINECS 247-777-4 Isodecyl alcohol, diphenyl phosphite Isodecyl diphenyl phosphite Mark 135A Phoselere T 26 Phosphorous acid, isodecyl diphenyl ester Weston DPDP, Chelating agent with metal carboxylates as polymer additives, especially for chlorinated polymers such as PVC and chlorinated PE Improves color, heat and light stability. Liquid bp = 190° d = 1,022-1.032 flash point = 154 . Akzo Chemie, Dover. 

Like heat and light stabilizers, flame retardants containing bromine or chlorine act as free-radical scavengers. They interrupt combustion essentially by replacing free hydrogen and hydroxyl radicals with halide (bromide or chloride) radicals that prevent the combustion reaction from continuing, according to a cyclic process (simplified here) ... 

Chem. Descrip. Epoxidized soybean oil CAS 8013-07-8 EINECS/ELINCS 232-391-0 Uses Plasticizer, heat/light stabilizer in flexible and semiflexible vinyl compds., PS, NBR, chlorinated rubbers for food pkg. and general use, and in coating vehicle systems Reguiatory FDA approved... 

Uses Chelating agent with metal carboxylates as polymer additives esp. for chlorinated polymers color, heat, and light stabilizer for PC, poly-... 

Toxicology TLV (Pb) 0.15 mg/m of air Uses Heat and light stabilizer, antioxidant for vinyl plastics and chlorinated paraffins in paints and plastics Lead phthalate, dibasic CAS 69011-06-9... 

Chen et a/ (1981) [201] studied the effect of decolorizing with NaOCl (5.25% available chlorine) on partly or fully stabilized acrylic fibers, heated for various times at 220-250°C. With lightly stabilized fibers, decolorization takes place in two steps—an incubation period with slight decolorization followed by a further incubation period and then gradual decolorization, whereas, with the fully stabilized fiber, the two processes occur simultaneously. 

Epoxy compounds. Epoxy compounds function both as plasticizers and stabilizers in flexible and semirigid PVC. As stabilizers, epoxies react with liberated HCl. In addition, they react with the polymer chain at labile-chlorine sites—either directly or catalytically by increasing the reactivity of the labile-chlorine site with metal salt stabilizers. Most epoxy stabilizers are derived from unsaturated fatty oils and fatty acid esters. Epoxidized soybean and linseed oils and epoxy tallate are commonly used products. Epoxy tallate also increases light stability. Epoxy compovmds can be formulated with metallic liquid stearates and, thus, can be sold to compounders as a one-package system if a constant ratio of stabilizer-to-epoxy is acceptable. However, since these epoxy compounds are also plasticizers, the balance of the formulation must be adjusted for this effect. 

Chlorinated polyethylene (CPE) modifiers have good impact resistance at low temperatures, chemical resistance, heat and light stability, and FDA clearance. These modifiers are most commonly used in pipe, fittings, siding, and weatherable profiles. CPE modifiers compete primarily with acrylics in siding applications. (See also chlorinated polyethylene.)... 

There are various additives in PVC plastics, such as antioxidants, light stabilizers, initiators, plasticizers, flame retardants, pigments and others. As initiators, potassium persulfate, benzoyl peroxide, lauryl peroxide, percarbonate and some azo-compounds can be used. The presence of chlorine in the hydrocarbon backbone gives rigidity and toughness to the polymer, but PVC liberates hydrogen chloride when exposed to high temperatures. To prevent this, stabilizers are added to the polymer. There are several kinds of stabilizers on the market. The most important contain lead, tin, calcium and zinc and... 

Vat Blue 6 (Pigment Blue 64) This chlorinated sister of Vat Blue 4 is greener in shade with good heat and light stability. It is used in olefinic applications where nucleation can be a problem. Melting point is >300°C. 

PVC plasticisers must be able to withstand normal processing temperatures up to 200°C without breakdown. Most commonly used plasticisers are reasonably heat stable, although the stabiliser content of a compound usually has to be increased when chlorine containing plasticisers such as chlorinated paraffins are used. Light stability and weathering resistance are also important. 

Complex compounds of chlorine, phosphorus and bromine have been developed for flameproofing polyester resins, polyolefins and polyurethanes. Unfortunately such compounds are usually toxic and expensive, and many of them, especially those containing hi proportions of bromine, suffer from poor heat and light stability. Considerable research effort is being expended to develop a broad spectrum, highly efficient heat and light stable flame retardant additive for plastics materials which could be sold at an economic price, but none of the products currently on the market fully satisfy all the requirements of an ideal flame retardant. 

The synthetic rubber chlorosulfonated poly-ethylene—(Hypalon —Du Pont Co., ceased operations April 20, 2010), also known as chlorosulfonyl polyethylene, introduced in 1952, is characterized by ozone resistance, light stability, heat resistance, weathering, resistance to deterioration by corrosive chemicals, and good oil resistance. Presently available types contain from 25% to 43% chlorine and... 

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