ISSN:0193-7197    

DOI:10.1002/vnl.730090202

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractA laser Raman spectroscopic study has been made of the effect of barium and cadmium stabilizers on the thermal dehydrochlorination of poly(vinyl chloride) (PVC). The results obtained indicate that, in terms of the total level of dehydrochlorination, cadmium stearate is not as superior to barium stearate as the visual appearance of the polymer suggests. Also, the level of dehydrochlorination produced in the presence of a mixed stabilizer is not significantly lower than that produced in the presence of barium stearate alone, while samples of the latter exhibit much stronger color. It has also been shown that cadmium stearate can reduce the length of long polyene sequences, presumably by a reaction near the center of such a sequence.

ISSN:0193-7197    

DOI:10.1002/vnl.730090203

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractOxytuf® mass polymerized PVC (IIP) contains grafted rubber moieties which provide for excellent impact resistance. The addition of a particulate filler to this resin with preservation of impact properties can be accomplished providing the particles are submicron and can be readily dispersed in the resin. Small particle size, surface treated, precipitated CaCO3, when added to IIP provided impact retention superior to that of a homopolymer control containing an added, non‐grafted impact modifi

ISSN:0193-7197    

DOI:10.1002/vnl.730090204

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractA brief historical review has been made of rheological instrumentation developed for measuring the flow properties of vinyl materials. During this maturation of techniques the need for more complete flow characterizations spawned the development of dynamic mechanical instruments. These instruments provided convenient and accurate means of generating complex viscosity (n*) data composed of elastic (G′) and (G″) elements. Examples have been presented illustrating how these newer techniques are able to reliably provide critical data needed to control productivity and product performance properties. Extension of these techniques to on‐line rheometry has improved quality control link in the compounding oper

ISSN:0193-7197    

DOI:10.1002/vnl.730090205

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractA comparison of acrylonitrile butadiene styrene (ABS) and chlorinated polyethylene (CPE) as PVC modifiers showed ABS to improve processability at low concentrations. CPE is more effective at high levels. Almost all the modifiers improved impact strength dramatically at 10 parts per hundred of resin. CPE containing 36 percent chlorine was the most effective, but reduced PVC modulus and heat‐deflection temperature more than AB

ISSN:0193-7197    

DOI:10.1002/vnl.730090206

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractPVC powder compound fed into single‐ and twin‐screw extruders retrofitted with cavity transfer mixers improved PVC grain fusion. Consequent improvements in appearance and properties ought to reduce current tight comprises that must be made between materials costs, output rate, and qual

ISSN:0193-7197    

DOI:10.1002/vnl.730090207

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractThe influence of the degree of plasticization on optimum heat‐sealing or high‐frequency welding conditions has been studied for plasticized PVC films with different quantities of DOP plasticizer. Two equations were obtained that relate the parameters of the welding process (time and temperature, or time and specific anodic current) with the degree of PVC film plasticization. The equations allow calculation of welding conditions needed to obtain maximum strength of welded joints. One describes the durability of lap joints; the other of T‐j

ISSN:0193-7197    

DOI:10.1002/vnl.730090208

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractMorphology and mechanical properties of blends of plasticized poly(vinyl chloride) (PVC) and thermoplastic copolyester elastomer (Hytrel 40D) have been studied with special reference to the effect of blend ratios. Morphology of the blends indicates that the Hytrel phase is dispersed as domains in the continuous PVC phase up to 75 percent of its concentration. Dynamic mechanical analysis of the blends shows marginal level of compatibility between the two phases. The mechanical properties depend on the proportion of thermoplastic rubber in the blend. Attempts have been made to correlate the blend morphology with properties. Failure surfaces were examined by scanning electron microscope and it was found that the fractographs depend on the type of failure (tensile or tear) and on the blend composition.

ISSN:0193-7197    

DOI:10.1002/vnl.730090209

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

摘要:

AbstractAlthough thermoplastic extrusion and injection molding have been extensively studied by a large number of authors, very little is known about the correlations between the extrusion and injection molding process variables. This paper describes the various comparable process variables between extrusion and injection molding of PVC dry blends. The Brabender extruder of 19 mm diameter and 25:1 length to diameter ratio and the Szekeley reciprocating single screw injection molding machine were used. PVC dry blends of industrial importance were prepared using a high speed mixer. The four mix formulations based on a commercial grade of PVC were used. Process variables studied during the injection molding were the melt temperature near the nozzle, injection pressure, injection speed, and energy consumption. Process variables studied during extrusion were the melt pressure at the die, power consumption, and the melt temperature at the die orifice. The correlations between the extrusion and injection molding process variables for PVC dry blends have been established.

ISSN:0193-7197    

DOI:10.1002/vnl.730090210

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY

ISSN:0193-7197    

DOI:10.1002/vnl.730090201

出版商:Society of Plastics Engineers    

年代:1987

数据来源: WILEY