Epoxide networks

Swelling experiments showed that a lignin epoxide resin of 0.11 epoxy equivalents per lOOg formed a network polymer when cured with DETA, PA, or ATBN. Phase separation was observed in the rubber-toughened lignin epoxide network. Cured epoxides had lignin derivative contents of up to 95%. 

The cyanate and the epoxide network can be bound by the reaction of phenolic hydroxyls contained in the partially cyclotrimerized cyanate prepolymer with the epoxy groups. In the first stage, a prepolymer was obtained by heating a mixture of BPA monocyanate and dicyanate with Co naphthenate as a catalyst (Scheme 15). 

It was traditionally believed that the ethylene epoxidation network was triangular with both ethylene and ethylene oxide contributing to CO2 (Fig, 1,5, Scheme 1). Cant and Elall studied the epoxidation of deuterium-labeled and unlabeled ethylene on silver catalysts and found an inverse isotope effect in... 

Resole/epoxide networks possess a higher crosslinking density and show a higher chemical resistance than novolacs crosslinfced with epoxides. Resole/epoxide networks have been applied as coatings. 

Nohales A, Lopez D, Culebras M, Gomez CM (2013) Rheological study of gel phenomena during epoxide network formation in the presence of sepiolite. Polym Int 62 397-405... 

In our previous works (7-9) siloxane-silica clusters formed by the sol-gel process from tetraethoxysilane (TEOS) were used to reinforce the rubbery epoxide network based on diglycidyl ether of Bisphenol A (DGEBA) and poly(oxypropylene)diamine (Jeffamine D2000). 

In some instances it is desired to produce a more open network from epoxide resins that have been acid-cured. This may be achieved by the oligoesterdi-carboxylic acids of general structure... 

Void-free phenolic networks can be prepared by crosslinking novolacs with epoxies instead of HMTA. A variety of difunctional and multifunctional epoxy reagents can be used to generate networks with excellent dielectric properties.2 One example of epoxy reagents used in diis manner is the epoxidized novolac (Fig. 7.34) derived from the reaction of novolac oligomers with an excess of epichlorohydrin. 

Epoxidized novolacs, 411 Epoxy -phenol networks, 411-416 properties of, 413-416 Epoxy-phenolic reaction kinetics of, 413 mechanism of, 411-412 Epoxy structures, 414 e-Caprolactam, 174... 

Organic Network Formers. As indicated above, an additional organic network can be built up by organic polymer synthesis within an inorganic network. The basic principles are shown in Equations 3 to 5 with a vinyl, methyl methacrylate and epoxide polymerization ... 

In this contribution, we report equilibrium modulus and sol fraction measurements on diepoxidet-monoepoxide-diamine networks and polyoxypropylene triol-diisocyanate networks and a comparison with calculated values. A practically zero (epoxides) or low (polyurethanes) Mooney-Rivlin constant C and a low and accounted for wastage of bonds in elastically inactive cycles are the advantages of the systems. Plots of reduced modulus against the gel fraction have been used, because they have been found to minimize the effect of EIC, incompleteness of the reaction, or possible errors in analytical characteristics (16-20). A full account of the work on epoxy and polyurethane networks including the statistical derivation of various structural parameters will be published separately elsewhere. 

A. Berkessel and J. A. Adrio, Dramatic acceleration of olefin epoxidation in fluorinated alcohols Activation of hydrogen peroxide by multiple H bond networks. J. Am. Chem. Soc. 128, 13412 13420 (2006). 

The chemical networks around a- and / -pinene are versatile. The four-membered ring is strained upon H+-catalysis an alkyl shift takes place and the bornyl cation is formed, which can enter various reactions. In contrast, the four-membered ring remains intact upon epoxidation or hydrogenation. 

M. Shimbo, M. Ochi and K. Aral, "Internal Stress of Cured Epoxide Resin Coatings Having Different Network Chains", J. of Coatings Technology, Vol. 56, 713, 45-51, June 1984. 

Dramatic Acceleration of Olefin Epoxidation in Fluorinated Alcohols Activation of Hydrogen Peroxide by Multiple Hydrogen Bond Networks... 

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