Vinyl composites

TrioctylPhosphate. Trioctyl phosphate [1806-54-8/, C24H 04P, has been employed as a specialty flame-retardant plasticizer for vinyl compositions where low temperature flexibHity is critical, eg, in military tarpaulins. It can be included in blends along with general-purpose plasticizers (qv) such as phthalate esters to improve low temperature flexibHity. 

Phosphate esters (alkyl or aryl, or mixed) of phosphoric acid constitute an important family of organophosphorus flame retardants.25 Triethylphosphate, a colorless liquid boiling between 209°C and 218°C, and containing 17 wt % phosphorus, has been used commercially as an additive for polyester resins/laminates and in cellulosics. In polyester resins, it functions as a viscosity depressant as well as a flame retardant. Trioctylphosphate is employed as a speciality flame-retardant plasticizer for vinyl composites where low temperature flexibility is critical. It can be also included in blends, along with general purpose plasticizers, such as phthalate esters, to improve low temperature flexibility. 

Fillers. Inert inorganic substances such as calcium carbonate, clay, silicates, and asbestos are often utilized in vinyl compositions where clarity is not a requirement. While the carbonates and clay are used ostensibly to reduce cost, beneficial results are forthcoming. The carbonates produce a dry, matte surface and are claimed, because of their alkaline nature, to benefit heat and light stability. Clay improves electrical insulation. Silicates enhance surface dryness. Asbestos fibers provide the reinforcement necessary for dimensional stability in floor tile. Antimony oxide, per se or as a surface coating on an inert carrier, provides flame retard-ance. Their only major adverse effects are to reduce tensile strength and elongation and require an increase in plasticizer level to compensate... 

The arsine-epoxy adduct provided exceptional protection for all plasticizers. Further, an epoxy-containing component must be included in a vinyl composition if optimum resistance to outdoor weathering is to be achieved (Table I). 

Brookfield, Ct., SPE, 2002, Paper 571, Session W7-Vinyl Plastics. Vinyl Composites, pp.5, CD-ROM, 012 EFFECT OF CALCIUM CARBONATE SIZE AND LOADING LEVEL ON THE IMPACT PERFORMANCE OF RIGID PVC COMPOUNDS CONTAINING VARYING AMOUNTS OF ACRYLIC IMPACT MODIFIER Bryant W S Wiebking H E Specialty Minerals Inc. 

For many years, di-2-ethyl hexyl phthalate has been the primary plasticiser for medical devices made of PVC, but there are concerns regarding its toxicity. The potential of a lesser used plasticiser, tributyl citrate, is examined. The properties of plasticised vinyl compositions were compared, including extraction, volatility, thermal stability, low temperature flexibility and mechanical properties. 12 refs. 

A Healthcare Provider Gains Strategic Marketplace Advantage. Kaiser Permanente, headquartered in Oakland, CA, a private not-for-profit healthcare provider serving 8 million members in 11 states and a leader in the healthcare delivery field, follows CSR recommendations wherever possible. Kaiser began efforts to replace PVC in carpets, vinyl composition tiles, and particleboard several years ago. 

These data underscore the principle that a vinyl composition must be completely fused before physical property measurements become meaningful (23). Relative fusion rates have been determined for a number of plasticizers, and the differences show that a preponderance of aromatic moieties in the plasticizer promotes fusion and favors processing. Thus, butyl benzyl phthalate fuses at a lower temperature than DOP diisodecyl phthalate fuses at a higher temperature. The relative fusion rates published for a variety of plasticizers provided valuable information for vinyl processors (T). Each plasticizer system for PVC must reach a specific minimum temperature in order to achieve complete plasticization. 

Figure 13 illustrates the elongation profile of the composition when three different plasticizers are used at increasing concentrations (37). Dioctyl adipate emerges from the antiplasticization area at relatively low concentrations and the elongation property builds steeply. The composition responds intermediately with increasing amounts of dioctyl phthalate, and dicyclohexyl phthalate is quite inefficient. When different plasticizers are substituted in a vinyl composition that must still maintain specific mechanical properties, the concentration of the substitutions must be adjusted to accommodate each particular plasticizer s "efficiency factor."... 

Recognition that heat stabilization of the plasticizer as well as the PVC resin was necessary greatly assisted researchers working on the problem. Epoxy compounds perform both functions. Today, they are part of many stabilization systems for vinyl compositions, so much so that worldwide use approaches 400 million pounds. In addition to vinyl stabilization, they are also used in phosphate ester functional fluids (i.e., fire-resistant hydraulic fluids) where acid development must also be avoided. 

Vinyl stabilizers can aggravate oxidation or Inhibit it. The same is true for pigments, some of which are prooxidants while others are antioxidants. To assure satisfactory odor in use, a chemically stable plasticizer should be selected the vinyl composition should be well stabilized during processing and antioxidants added to the formulation, if not already present in the "stabilizer package" used. To assess potential odor development, it is prudent to test every new vinyl formulation by heating in a closed bottle at 50 C for several days. 

Only in exceptional short-lived applications are volatile plasticizers useful. Certain dihexyl phthalates are sufficiently low in volatility to be satisfactory for use in noncritical applications. Volatility loss from vinyl compositions is directly related to a plasticizer s vapor pressure and oxidation resistance. These are dependent upon molecular weight and structure. The effect of molecular structure can be illustrated with two isomeric dioctyl phthalates. Figure 16 shows that the straight chain ester with half the volatility confers much improved low-temperature flexibility compared with the branched structure. 

These figures also illustrate the importance of matching test conditions to the conditions encountered in service. This reasoning applies also to factors not referred to in fig. I. such as the surface condition of the materials being te.sted. a point emphasised by James and Mohsen [2]. Similarly, a method of bringing an Official vinyl Composition Tile to a standard condition is described in ASTM D4103-90 [.3],... 

Uses Plasticizer for acrylic coatings where UV stability is important extrusion aid in rigid vinyl compositions inj. molding aid in PC, PP compds. to reduce cycle time food pkg. adhesives Reguiatory FDA 21 CFR 175.105... 

Table 2.5 Heat release and smoke data (ASTM) for glass/vinyl composites with additives ...

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