摘要:

AbstractPolyvinylidene chloride (PVDC) copolymers are highly crystalline materials used in packaging applications because of their strength and excellent barrier properties. The crystalline moiety (∼40 to 50%) generally melts from 160 to 170°C and the amorphous phaseTgis between 0 and 35°C depending on the comonomer type and level. PVDC is much less thermally stable than PVC and degrades very rapidly in the same temperature range (i.e. above theTm) required to process the material. Added plasticizers are utilized to reduce processing temperatures but at the expense of barrier properties. There is a need to process PVDC sans plasticizer to achieve maximum possible barrier properties in multilayer composite sheet and films. Additives will be discussed that have been shown (in laboratory tests) to delay the fusion of the amorphous phase of unplasticized PVDC until the material temperature nears the crystalline melting point, thus reducing the overall heat history with a minimal effect on other important propert

ISSN:0193-7197    

DOI:10.1002/vnl.730160112

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractTrimethylpentane diol (TMPD) dibenzoate use in vinyl as a plasticizer is not well recognized, and little has been published on vinyl performance characteristics. To assess new applications for vinyl, a basic evaluation was conducted. Based on the results of the screen and other considerations an evaluation for utility in plastisol silk screen ink was conducted. The results indicated that the TMPD dibenzoate performed very well in white ink, requiring good fabric dye bleed resistance compared to polymeric and phthalates currently being used for non‐bleed ink. Non‐bleed characteristics are important for colored tee shirt printing. The benzoate is a good solvator and has excellent extraction resista

ISSN:0193-7197    

DOI:10.1002/vnl.730160113

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractThe diffusion of a plasticizer S1from a source made of PVC containing 25 wt% of S1into a medium made of PVC film containing another plasticizer S2in 15, 20, 25 and 30 wt%, was studied at temperatures ranging from 70 to 108°C. S1was generally diphenyl‐iso‐octyl phosphate (DPIP) and S2was dioctyl phthalate (DOP) but the reciprocal system was also studied in some cases. Starting from a reference point corresponding to a temperature of 70°C and a DOP concentration of 25 wt%, it was found experimentally that an increase Δvof the DOP volume fraction (v) or an increase ΔTof the temperature, led to the same variation of the diffusion coefficient of DPIP if ΔT/Δv∼ 139K. A reasonably close value can be obtained from a simple free‐volume approach, using the literature data on the plasticizer action

ISSN:0193-7197    

DOI:10.1002/vnl.730160114

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

摘要:

AbstractA central composite design of experiment as used to study the effect of five additives on the fusion characteristics of a rigid PVC compound. The fusion characteristics evaluated were fusion time, fusion torque, and fusion temperature as measured by a torque rheometer. Mathematical models were constructed for the following five independent formulation variables: impact modifier, paraffin wax, calcium stearate, ester wax, and processing aid. Because of differences in the lubricating properties of these additives, mathematical modeling can help the manufacturers of rigid PVC products to understand and better formulate necessary changes to optimizes the performance requirements of their end use products. The ability to predict the fusion characteristics of a proposed formulation change will help minimize the number of required production evaluations.

ISSN:0193-7197    

DOI:10.1002/vnl.730160115

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY

ISSN:0193-7197    

DOI:10.1002/vnl.730160101

出版商:Society of Plastics Engineers    

年代:1994

数据来源: WILEY