摘要:

AbstractMoisture present in epoxy anhyride composites may hydrolyze the anhydride and cause major changes in the mechanical and chemical properties of the final composite. Heat distortion data and infrared spectroscopy are used to analyze the changes caused by the presence of the moisture. As the concentraton of water is increased, there is a decrease in the heat distortion or gass transition temperature. The decrease is due to a change in the crosslinking network and is caused by the reduction of the functonality of the epoxy group for acid as compared to the anhydride. Where rigid specifications must be met it is essential that the moisture level in the fillers, resins, etc. be kept constant.

ISSN:0032-3888    

DOI:10.1002/pen.760060112

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY

摘要:

Abstract2‐Ally‐1‐methylenecyclohexane is a compound which is functionally capable of undergoing polymerization by the alternating intra‐intermolecular propagation mechanism to produce poly[1,8‐methylene[4.3.0] bicyclononane]. This monomer was synthesized and its polymerization through use of cationic and Ziegler‐type initiators was studied. Synthesis of the monomer was accomplished by the following reaction sequence: (1) conversion of cyclohexanone to 2‐allycyelohexanone by reaction wtih allyl bromide and sodium amide and (2) conversion of 2‐allycyclohexanone to the desired monomer by reaction with the phosphorane derived from methyltriphenylphosphonium bromide. Polymerizaton was accomplished by use of boron trifluoride resulting in 44% conversion to polymer, of which 94% was soluble. Through use of infrared and nuclear magnetic resonance techniques, the soluble portion of the polymer was shown to contain 54% of bicyclic units and the remainder to be non‐cyelized monomer units in which the residual unsaturation was composed predominantl

ISSN:0032-3888    

DOI:10.1002/pen.760060113

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY

摘要:

AbstractThe resistivities of commercial octyl phthalatel plasticizers have been measured after treatments of heating, drying, purification by chromatography and addition of salts. The resistivity of pure plasticizer is high but is lowered by water, acid and alcohol. The theory to explain the observations is advanced.

ISSN:0032-3888    

DOI:10.1002/pen.760060114

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY

摘要:

AbstractThe determination of the state of resin advancement in asbestos‐phenolic prepregs is important to the processor of this material. Many tests have been proposed for measuring this condition. In this article the follwing tests were made on the prepreg and resin extracted from the prepreg to measure advancement: viscosity, Chang Index,‐infrared absorption dielectric constant, dissipation, dielectric constant, and dissipation factor, volume resistivity, and tear strength. Infrared absorption, dielectric constant, and dissipation factor correlated best and were the most sensitive indicators of resin advancem

ISSN:0032-3888    

DOI:10.1002/pen.760060115

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY

摘要:

AbstractSome recent observations of catastrophic yielding or bimodal flow behavior in linear polyethylene melts have indicated certain inadequacies in the commonly accepted flow theories and practices. Examples of some “non‐ideal” behavior are presented along with some evidence that slip at or near the polymer‐die interface, rather than a flow phenomenon, is the mechanism associated with the discontinuity in the flow curve. The discontinuity shear stress is observed to be independent of hydrostatic pressure. The significance of this bimodal flow behavior is related to polymer processing p

ISSN:0032-3888    

DOI:10.1002/pen.760060116

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY

ISSN:0032-3888    

DOI:10.1002/pen.760060101

出版商:Society of Plastics Engineers, Inc.    

年代:1966

数据来源: WILEY