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ABS/PVC blends

Bromine compounds are often used as flame retardant additives but 15-20ptsphr may be required. This is not only expensive but such large levels lead to a serious loss of toughness. Of the bromine compounds, octabromo-diphenyl ether has been particularly widely used. However, recent concern about the possibility of toxic decomposition products and the difficulty of finding alternative flame retarders for ABS has led to the loss of ABS in some markets where fire retardance is important. Some of this market has been taken up by ABS/PVC and ASA/PVC blends and some by systems based on ABS or ASA (see Section 16.9) with polycarbonates. Better levels of toughness may be achieved by the use of ABS/PVC blends but the presence of the PVC lowers the processing stability. [Pg.444]

Blending of ABS with other polymers is not restricted to the aim of raising the distortion temperature. Blends with PVC are made for various purposes. For example, 80 20 ABS/PVC blends are used to produce fire-retarding ABS-type materials, as already mentioned, while 10 90 blends are considered as impact-modified forms of unplasticised PVC. ABS materials have also been blended with plasticised PVC to give a crashpad sheet material. [Pg.446]

Cortes et al. [975] have used on-line p,SEC-CGC for rapid determination of a great variety of additives in an emulsion ABS-PVC blend, HIPS and a styrene-acrylate-ethylene rubber polymer. These systems are difficult to analyse, because of the high levels of insolubles such as fillers, pigments, or rubber modifiers. The additives were separated from the polymer fraction in a polymer/additive dissolution using p,SEC, and were... [Pg.556]

ABS/PVC blends (e.g., Triax CBE, Enplex tm) are formulated to provide a broad window of molding conditions. Because of the presence of PVC, shear or thermal degradation must be minimized. Shot size should be about 50% of machine capacity — less than 35% will result in a long residence time, whereas in excess of 65% will increase plasticating time, both of which create conditions for resin degradation. High compression screws should be avoided since they generate excessive shear heat — a linear taper screw with a compression ratio between 1.5 and... [Pg.712]

In Enplex ABS/PVC blends, ABS contains some a-methyl styrene and a methylmethacrylate, MMA, copolymer. An in-line screw injection machine for molding general-purpose ABS, PS and similar resins can be used. The machine should have multi-stage injection speed control unit and a cooling blower unit to control shearing... [Pg.712]

PVC/PU blends were compoimded from rigid and plasticized PVC (plasticized PVC contained 36 phr DOP). Figure 12.7 shows that elongation behavior of two blends is dramatically different. It is suspected that the plasticizer helps in the compatibilization of blend components. The blend with plasticized PVC appears to be uniform on the macroscopic scale. Addition of DOP to ABS/PVC blend improved impact strength and elongation but hardness, tensile strength, and Young modulus were reduced."... [Pg.386]

An Analysis of the Thermal Degradation Under Processing Conditions of ABS/PVC Blends... [Pg.255]

The present evidence indicates what phases are being degraded but does not indicate how this occurs. In thefuture more work will be done to elucidate both the mechanism and develop a stabilizer package for the blend. In the meantime in order to avoid product embrittlement, due care must be taken to process the ABS/PVC blends at ZOO C or less. [Pg.262]

Precompounded blends of ABS and PVC have also been commercially available for molding and extrusion applications as low-cost alternatives to flame-retarded grades of ABS and PPE/HIPS blends. Commercial ABS/PVC blends offer... [Pg.1770]

ABS/PVC blends have found use in applications requiring flame-retardant characteristics, e.g., in appliances, business machine housings, TV-cabinets, electrical and electronic components. The blends show excellent moldability. [Pg.30]

It has been found that incorporating modest amounts of hydrated iron(m) oxide (FeOOH) into ABS/PVC blends increases char formation significantly when compared with equivalent formulations containing no iron. The formation of large amounts of char in the presence of basic iron(m) oxide results in a reduction in the amount of smoke produced when the polymer blend bums in air. In addition to the formation of char, it has also been found that this iron(iii) compound improves the flame resistance of the blends and also stabilizes them against decomposition by both heat and light (Table 1). [Pg.310]

Figure 3 Percentage char versus percentage chlorine in ABS/PVC blends. Figure 3 Percentage char versus percentage chlorine in ABS/PVC blends.
Recent work on char formation in ABS/PVC blends carried out in our laboratory suggests that char formation is dependent upon the PVC content and in the iron containing polymer blends, char formation depends not only on the PVC content, but also on the Fe/Cl stoichiometry... [Pg.312]

It is now thought that iron smoke suppressants reduce smoke in these ABS/PVC blends probably by a combination of two important processes ... [Pg.313]

The properties of ABS/PVC blends exhibit weathering behavior similar to those of ABS yellowing and brightening take place [83]. [Pg.499]


See other pages where ABS/PVC blends is mentioned: [Pg.326]    [Pg.32]    [Pg.1046]    [Pg.1046]    [Pg.1046]    [Pg.1046]    [Pg.965]    [Pg.109]    [Pg.342]    [Pg.257]    [Pg.259]    [Pg.261]    [Pg.46]    [Pg.47]    [Pg.1770]    [Pg.1770]    [Pg.1771]    [Pg.2281]    [Pg.66]    [Pg.3]    [Pg.172]    [Pg.220]    [Pg.61]    [Pg.184]   
See also in sourсe #XX -- [ Pg.447 ]

See also in sourсe #XX -- [ Pg.331 ]

See also in sourсe #XX -- [ Pg.447 ]

See also in sourсe #XX -- [ Pg.447 ]




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ABS blends

PVC blends

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