ISSN:0032-3888    

DOI:10.1002/pen.760010202

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

ISSN:0032-3888    

DOI:10.1002/pen.760010203

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractDerivatives of 2‐hydroxybenzophenone are well‐known stabilizers for such polymers as cellulose acetate butyrate and polyesters. Their stabilization effectiveness is commonly associated with their ability to screen a polymer from the harmful ultraviolet radiation found in sunlight. They also satisfy other requirements for effective stabilizers, namely, compatibility with many polymers and an inherent stability to ultraviolet light. Several other functions of 2 hydroxybenzophenones in stabilizing a polymer to ultraviolet light have been postulated, but little experimental data related to them are available. This paper deals with some of the additional functions of 2‐hydroxybenzophenones in weathering stabilization as investigated by nuclear magnetic resonance spectroscopy (NMR) and electron paramagnetic resonance spectroscopy

ISSN:0032-3888    

DOI:10.1002/pen.760010204

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractA new method for measuring heat stability and temperature of degradation of thermosetting plastics is described, as well as an improved method for the determination of transition temperature into glassy or viscous state for thermosetting resins. Magnitude of elastic deformation is tied in with length of polymer chain and lattice density.

ISSN:0032-3888    

DOI:10.1002/pen.760010205

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractDuring the last thrity years, dielectric measurements have been employed extensively to provide a better understanding of the interactions between polymer and plasticizer in various thermoplastic formulations. Recently, a series of melamine resins, plasticized to the extent that shrinkage and internal stress were modified, became available. Since there is little information in the literature concerning the dielectric properties of such thermosetting resins, a study was made of the variation of dielectric constant and loss as a function of frequency and temperature.

ISSN:0032-3888    

DOI:10.1002/pen.760010206

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractThis article includes a comparison of the adhesive properties of bisphenol‐A expoxides at 300°K and 76°K with respect to the molecular weight of the uncured resins. Joints of 2024 aluminum were tested at 300°K and 76°K in tensile‐shear and in impact‐shear, and total linear thermal contraction of the cured resins was measured between the two temperatures. Results are discussed with respect to residual joint stresses and adsorptive properties of t

ISSN:0032-3888    

DOI:10.1002/pen.760010207

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractThe magnitude and temperature dependence of the electrical resistivities of a number of thermoplastic and thermosetting high polymers have been determined. Activation energies for the electrical conduction process Eehave been calculated and found to vary from 12 to 60 Kcal/mole depending upon the structure of the polymer. Results are interpreted in terms of an ionic diffusion process and discussed in terms of the structure of the polymers.

ISSN:0032-3888    

DOI:10.1002/pen.760010208

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractFor broad ranges of operating conditions and a wide variety of high pressure polyethylenes, the flow data obtained from a high shear viscometer and a commercial extruder are identical. Discrepancies between flow data can result from non steady state viscosities in the high shear viscometer, or from cooled screw extruder operation. In the broad regions in which the flow data concur, the readily obtained viscometer data are suitable for predictions of extruder performance. The principle is illustrated by the good correlation of a viscometer flow curve parameter and the screw power consumption in the extruder. Principles outlined for flow data identity and extruder performance prediction are believed to be general, but the quantitative limits defined are specific to the extrusion devices involved.

ISSN:0032-3888    

DOI:10.1002/pen.760010209

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

摘要:

AbstractRecent technology has evolved a number of dissimilar thermoplastics which under conditions of ambient temperature and impact loading show both the high modulus, which is mainly a property of brittle polymers in the glassy state, and also the impact resistance, such as may be expected of polymers in the rubbery state. Several of these special plastics were examined by electronmicroscopy and also with respect to several aspects of their mechanical behavior to establish by direct observation and inference whether or not different types of plastics exhibit some common features of structure which promote impact resistance. These observations suggest the hypothesis that special circumstances of domain heterogeneity can override many other variables of composition or molecular structures in controlling the fracture mechanism.

ISSN:0032-3888    

DOI:10.1002/pen.760010210

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY

ISSN:0032-3888    

DOI:10.1002/pen.760010201

出版商:Society of Plastics Engineers, Inc.    

年代:1961

数据来源: WILEY