摘要:

Mechanical properties of polypropylene (PP) filled with wood flour was studied. To improve adhesion at the interface, different surface treatments of the fiber were carried out. Polymethylene polyphenylisocyanate (PMPPIC) and silane coupling agents (silane A-172, A-174, and A-1100) were used to pretreat the fiber before it was introduced into the polymer. Increase in tensile strength, with fiber concentration, was found in PP filled with PMPPIC pretreated wood flour. Elastic modulus was unaffected by fiber treatment. Izod-impact strength decreased with increased filler level in the composite.

ISSN:0360-2559    

DOI:10.1080/03602558908048598

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The retarding and the accelerating activities of some modified thiocarbamyl sulfenamides—namely,N-cyclopentamethylene thiocarbamyl-N′-(cyclohexyl, thiocyclohexyl) sulfenamide (CPCTS),N-cyclopenta-methylenethiocarbamyl-N′-(cyclohexyl,N-cyclopentamethylene thio) sulfenamide (CPCCS), andN-cyclopentamethylenethiocarbamyl-N′-(cyclohexyl,N-oxydiethylene thio) sulfenamide (CPCOS)—have been studied in dibenzothiazyl disulfide (MBTS)-accelerated vulcanization of natural rubber (NR). It is found that CPCTS, CPCOS, and CPCCS delay the onset of cure and generate active accelerators during vulcanization. In addition to this, the accelerator systems are quite capable of producing age-resistant vulcanizates. The results indicate that thiocarbamyl sulfenamides modified chemically at the >NH functionality retain their accelerating property. Thus CPCTS, CPCOS, and CPCCS play the dual role of an accelerator and a retarder in the vulcanization of NR accelerated by MBTS.

ISSN:0360-2559    

DOI:10.1080/03602558908048599

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Structural RIM is an ideal replacement for structural steel and other composites because of its lightweight, high flex modulus, and high volume production capability. Important to the successful production of SRIM is utilization of the proper equipment to handle high volumes of parts. Besides developing new metering units and clamps for SRIM processing, extensive work has been done in the area of preforming. A variety of preformers have been developed to meet the needs of the different types of glass mats. The goal of this article is to discuss all of the equipment used in SRIM processing: the metering unit, clamp, and preformer. The article then discusses a turnkey system that integrates all the specific components to give a rapid automatic system for the rapid production of SRIM parts.

ISSN:0360-2559    

DOI:10.1080/03602558908048600

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Emulsion copolymerization of a moderately water-soluble monomer (ethyl acrylate) with a completely water-soluble monomer (methacrylic acid) was initially examined in a batch reaction system. The reaction rates, copolymer composition, and physical properties of the latex product were characterized. Batch reactions were run with various monomer ratios. The latex stability was strongly dependent on both the temperature and the overall fractional conversion. Several continuous processes involving a tubular reactor and/or a continuous stirred-tank reactor were designed and utilized so as to produce a latex product with properties similar to the batch product.

ISSN:0360-2559    

DOI:10.1080/03602558908048601

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Experimental and modeling studies of the free-radical-induced degradation of polypropylene (PP) in the melt phase have been carried out. Experiments have been performed in a single-screw plasticating extruder using a peroxide as the free-radical source. Concentration of the peroxide was in the range 0.01–0.6 wt%. Results in the form of melt flow index (MFI) values, viscosity curves, and molecular weight distribution (MWD) of the produced resins are presented here. Based on these results, a constitutive equation describing the shear viscosity of the melt as a function of shear rate, temperature, and molecular weight has been derived. The extensional viscosity of these resins has been determined as a function of strain rate using Cogswell's analysis of converging flows. A previously developed kinetic model (plug flow) has been used to simulate the changes of the average molecular weights of the MWD, and a sensitivity analysis of this model has been carried out.

ISSN:0360-2559    

DOI:10.1080/03602558908048602

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0360-2559    

DOI:10.1080/03602558908048597

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor