摘要:

AbstractThe radiation crosslinking (via Co60) of both high and low density polyethylene in the presence of several tetrafunctional monomers has been studied to observe the effects of the additives on mechanical and electrical properties. The monomers employed were allyl methacrylate, divinylbenzene, and diallyl maleate. Monomer levels were such that the number of moles presented per number‐average mole of polyethylene was 2.2–2.6 for AMA and DVB with Marlex 5003 and 6009, and 9–10 for Marlex 1712. The DAM level was 3–5% of that of the other monomers on the same basis. Gel fractions, tensile strengths (at yield and break) at ambient temperature and tensile strengths, elongations, and moduli measured at a temperature above which no crystallinity remains all undergo more marked changes in the presence of tetrafunctional monomer after only 1–3 Mrad of radiation, regardless of monomer nature. Gels, tensiles, and moduli increase while elongation decreases. The magnitude of the changes depends upon the monomer nature (at the above ratios), the order being AMA>DVB>DAM>Monomer‐free. With increasing does to 8 Mrad, the trends continue. The gel swelling ratios are inversely proportional to the 3/5 power of the crosslink density, as determined by the modulus value in the absence of crystallinity. Straight radiation of monomer‐free polyethylene to higher doses not necessarily yield physical properties values attained at the lower doses with additive. The dielectric constant and dissipation factor of monomer‐containing crosslinked polyethylene are only slightly affected by the presence of the polyfun

ISSN:0021-8995    

DOI:10.1002/app.1966.070100111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1966

数据来源: WILEY

摘要:

AbstractThe torsional braid experiment of Lewis and Gillham has been so modified that kinetic parameters can be obtained in polymerizations conducted with viscous prepolymers. The relative rigidity curve is interpreted in terms of extent of cure. The activation energy for the polymerization of a carboxyl‐terminated polybutadiene with an aziridinyl compound has been measure

ISSN:0021-8995    

DOI:10.1002/app.1966.070100112

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1966

数据来源: WILEY

摘要:

AbstractThe effect of solubilization of latex polymers was investigated in various anionic surfactant solutions. The process of solubilization was studied by measuring the increase in light transmission and viscosity of the latexes. It was found that anionic surfactants differ widely in their ability to solubilize a given polymer, and susceptibility to solubilization is significantly affected by comonomer content of the polymer. If, for example, a poly(vinyl acetate) latex is stabilized exclusivdly by a strongly solubilizing sodium dodecyl benzene sulfonate, it is less stable and hydrolyzes faster than a similar latex made with a polyoxyethylene derivative, which has only a slight solubilizing action. Dibutyl mateate copolymers of vinyl acetate are less susceptible to solubilization than hompolymers of vinyl acetate.

ISSN:0021-8995    

DOI:10.1002/app.1966.070100113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1966

数据来源: WILEY

摘要:

AbstractThe permeation of water through glyceryl methacrylate (2,3‐dihydroxypropyl methacrylate) and 2hyphen;hydroxyethyl methacrylate hydrogels was increased by the incorporation of silica fillers. Both the amount of water at equilibrium and the amount of filler in the gel contribute to increase the permeability of these membrane

ISSN:0021-8995    

DOI:10.1002/app.1966.070100114

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1966

数据来源: WILEY