ISSN:0193-7197    

DOI:10.1002/vnl.730160102

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

ISSN:0193-7197    

DOI:10.1002/vnl.730160103

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractA common assumption in mold filling analysis is that the molding machine is capable of providing a fully pressurized uniform temperature melt to the rear orifice of the sprue. Based upon this assumption, the finite element model then only represents the geometry of the mold itself from the sprue rear orifice forward. This assumption, however, is acceptable only when the injection modeling machine nozzie extension is of such a length that the pressure drop in the nozzle is negligible. For large injection molded parts the exclusion of the molding machine nozzle in the design phase of the mold filling analysis may produce overly optimistic results. This study of an actual large (7.9 kg) injection molded thin wall (4 mm) vinyl part will show the effects of nozzle length on the accuracy of mold filling analysis software predictions. Analytical results with and without representation of the molding machine nozzle in the finite element model will be compared to production trial results.

ISSN:0193-7197    

DOI:10.1002/vnl.730160104

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractIn July 1992, the U.S. Federal Trade Commission (FTC) issued its long awaited guidelines on the use of environmental marketing claims. These guidelines do not carry the force of law, but they may result in law enforcement action if such claims are found to constitute deceptive advertising. The paper examines the effect the FTC guidelines will have on the marketing of vinyl products. It briefly describes the general principles that apply to all environmental marketing claims and then discusses the eight specific claim types covered by the FTC document: general environmental benefits, degradability, compostability, recyclability, recycled content, source reduction, refillability, and ozone friendliness.

ISSN:0193-7197    

DOI:10.1002/vnl.730160105

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractThe technology for extruding rigid cellular PVC has grown substantially over the past decade. Formulation additives, tooling, and processing expertise have made possible a variety of applications—relatively complex profiles, foam‐core pipe, thermoformable foam sheet, and house siding. In the U.S. market, vinyl house siding is typically a relatively thin extrusion that is folded into a final shape that resembles wood cladding in appearance. An alternative to conventional form vinyl siding could be a foam structure that is thicker and stiffer than the solid form, and with a density similar to that of wood. This paper presents several performance advantages of rigid cellular PVC cladding in comparison to the current solid product, in addition to mentioning certain limitations that exist in the foam product that is produced with the technology available to

ISSN:0193-7197    

DOI:10.1002/vnl.730160106

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractEthylene copolymer resin (ECR) modifiers, designed to be soluble in all proportions in PVC, form a wide variety of plasticized PVC blends. These solid, high molecular weight (Mw>250,000) resin modifiers, unlike conventional liquid plasticizer, exhibit outstanding permanence in PVC. Compounding procedures, used for liquid plasticized PVC, are sometimes inadequate to produce homogeneous blends of PVC/ECR. A number of effective melt compounding techniques and a new family of ECR modifiers have been developed to produce homogeneous blends exhibiting many outstanding properties, including fluids/chemical resistance, high/low‐temperature service, and weatherabilit

ISSN:0193-7197    

DOI:10.1002/vnl.730160107

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractThis paper is on the enhancement of physical properties achieved through utilization of linear plasticizers in flexible PVC compounds. This paper also emphasizes the use of statistical methods and designs of experiments. In a series of experimental designs, electrical, oven‐aging, and low temperature performance of commercially available phthalate plasticizers were evaluated. Test data will be given to show the effect of plasticizer functionality on the performance properties of flexible PVC compound

ISSN:0193-7197    

DOI:10.1002/vnl.730160108

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractDOA, (di‐2‐ethylhexyl) adipate, is a monomeric ester plasticizer frequently used in PVC compositions to enhance flexibility at low temperatures. DOA has several drawbacks; it lacks permanence in the PVC matrix and it has poorer compatibility than its phthalate homologue (DOP). By reacting adipic acid with polyols, polymer chains of increased molecular weights can be formed. These polyester plasticizers offer increased permanence over DOA. The focus of this paper is to demonstrate how adipate plasticizers, starting with DOA and increasing in molecular weight, affect the performance of flexible vinyl, especially in regard to UV resistance and permanence. The following series of evaluations will show that as the molecular weight of plasticizers increases, the permanence properties (volatility and extraction by various media) increase. The ability to withstand degradation from ultraviolet light also increases with higher molecular wei

ISSN:0193-7197    

DOI:10.1002/vnl.730160109

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractCrystallinity in PVC contributes significantly to the strength and resiliency of the polymer. Two types of crystallites have been described: a primary crystallite in the virgin powder state pictured as a platelet or flat needle‐like lamellar crystallite, and a secondary, fringed micellar crystallite from melts or solutions. Both crystallites create loose, crosslinking networks. The secondary crystallite forms when plastisol melts are cooled or solutions are gelled. Crystallites exert a major effect on rheological properties. The thermal destruction of the primary crystallite networks in the melt phase results in a decrease in elastic modulus. Cooling from the fused state creates secondary crystallites that affect tensile and elongatio

ISSN:0193-7197    

DOI:10.1002/vnl.730160110

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractBulk density is one of the easiest measured and most practical physical properties of PVC resins and compounds, especially those used in rigid applications. The paper addresses the importance of bulk density of rigid PVC resins, both regular and antistat, and their compounds. The negative influence of static electricity on bulk density measurement of PVC resins is studied and discussed. Effective static removal and accurate, consistent bulk density measurement is explored through various methods such as compacted bulk density and conditioned bulk density (either by addition of silica, methanol or carbon black, or by treatment with an ionizer).

ISSN:0193-7197    

DOI:10.1002/vnl.730160111

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY