Epoxy constituents

The effect of the epoxy constituent is particularly pronounced where the trialkyl phosphate is a major component of the primary plasticizer system (Table IV). 

Preparations containing epoxy constituents with an average molecular weight < 700... 

Contains epoxy constituents. See information supplied by the manufacturer. ... 

EUH205 Contains epoxy constituents. May produce an allergic reaction. 

A great variety of resia formulations is possible because other thermosets, such as epoxies or acrylates, and reactive diluents, such as o-diaUyl phthalate [131-17-9] triaUyl cyanurate [101-37-17, or triaUyl isocyanurate [1023-13-6J, can be used to further modify the BT resias. The concept is very flexible because bismaleimide and biscyanate can be blended and copolymerized ia almost every ratio. If bismaleimide is used as a major constituent, then homopolymerization of the excess bismaleimide takes place ia addition to the copolymerization. Catalysts such as ziac octoate or tertiary amines are recommended for cure. BT resias are mainly used ia ptinted circuit and multilayer boards (58). 

Fig. 11 presents the variation of the various moduli of the composite and its constituents for various volume fractions of the series of iron-epoxy particulates. 

Fig. 16. The variation of the moduli of the constituent phases and the composite versus the fiber volume content for a series of E-glass-epoxy fiber reinforced composites...

Due to the chemical structure, fimctionality and composition of their constituents, ordinary variations of the processing conditions as well as the quality of the raw materials have been observed to lead to changes of the fine structure which are often responsible of lower ageing resistence of the polymer. The data reported here correlate the morphology of some widely utilized epoxy matrices to the informations that can be obtained from the study of the sorption behaviours. 

Epoxy resins find a large number of uses because of their remarkable chemical resistance and good adhesion. Epoxy resins are excellent structural adhesives. When properly cured, epoxy resins can yield very tough materials. They are used in industrial floorings, foams, potting materials for electrical insulations, etc. One of the principal constituents in many of the Fibre-reinforced plastics (FRP) is an epoxy polymer. 

Three workers applying an epoxy-based waterproofing paint containing glycidyl ether inside an underground water tank died in the tank of asphyxia. Constituents of epoxy resin will displace oxygen in a confined space and may have an independent narcotic effect on exposed workers. Strict precautionary measures are recommended under these conditions. ... 

Uses. Hardener/cross-linker for epoxy resins metal chelator constituent of wet-strength paper resins copolymer with fatty acids in metal spray coatings constituent of synthetic elastomer formulations... 

Fukuzumi, and M. Noguchi. Isolation of a new tobacco constituent, (3S,5R, 6S,9Zeta)-3 -hydroxy-5,6-epoxy-be ta-ionol, from Japanese domestic suifu tobacco. Agr Biol Chem 1978 42 1785-1787. 

Non-volatile constituents in tobacco. Part 1. Isolation of a new terpene clucoside,3-hydroxy-5,6-epoxy-beta-ionyl-beta-D-glucopyranoside from flue-cured tobacco. Agr Biol Chem... 

NT552 Wahlberg, I., D. Behr, A. M. Eklund, T. Nishida, C. R. Enzell, andj. E. Berg. Tobacco chemistry. 54. (1S,2E,4S,6E, 8S,1 IR,12S)-8-l1-epoxy-cembradiene-1,12-diol, a new constituent of Greek tobacco. Acta Chem Scand Ser B 1982 36 37—41. 

C-5 epimers of 6,7-didehydro-5,6,5, 6 -tetrahydro-)3,/3-carotene-3,5,3 5, 6 -pentol (15), isolated as minor constituents of a sample of neoxanthin [5, 6 -epoxy-6,7-didehydro-5,6,5, 6 -tetrahydro-j8,j8-carotene-3,5,3 -triol (16)] from Trollius europaeus, may be artefacts. In Sarcina lutea, sarcinaxanthin [2,2 -bis-(4-... 

These compounds are almost exclusively accumulated in aerial parts and leaves from genera of the Rutaceae such as Bosistoa, Boronia, and Melicope, and rarely in Euodia and Zanthox-ylum. There is a strong tendency towards prenylation at the 7-OH or 4 -OH group. From aerial parts of Boronia coerulescens, a derivative with 3,4 -(9-prenylation was also described (compound 130, Table 12.4). Similarly, only one C-6-(9-derivative was reported from the aerial parts of Melicope. Two 7-epoxy derivatives have already been listed in the previous survey. Combination with methylenedioxy substitution is less frequent, concerning a few sources of Rutaceae and Asteraceae only. Probably, these constituents are partly accumulated externally. 

It is clear that other components quite different chemically from the main constituents of the epoxy resin system may be present in the starting material. The structure of the cured epoxy may or may not incorporate these components. To the extent that these other species are not part of the crosslinked epoxy network, they can be concentrated at the interphase or they may be able to migrate to the interphase during the curing process. 

Consider the same unidirectional lamina with the stresses now applied perpendicular to the fiber axis as shown in Fig. 12. The local stress at the fiber matrix interface can be calculated and compared to the nominally applied stress on the whole lamina to give K, the stress concentration factor. The plot of the results of this analysis shows that the interfacial stresses at the point of maximum principal stress can range up to 2.6 times the applied stress depending on the moduli of the constituents and the volume fraction of the reinforcement. For a typical graphite-epoxy composite, with a modulus ratio of 70 and a volume fraction of 70 % the stress concentration factor at the interface is about 2.4. That is, the local stresses at the interface are a factor of 2.4 times greater than the applied stress. 

Among other reactions, the synthesis of the epoxide-N-oxide from retronecine should be mentioned82 the epoxide yields rosmarinecine on hydrogenation over Raney nickel (see Section III, A). The epoxy group has been recently demonstrated to be a constituent of certain... 

In this Sect, we report systematic DSC studies of (i) the constituents of boron tri-fluoride monoethylamine (BF3 NH2C2H5) catalyzed TGDDM-DDS epoxies and their mixtures (ii) the nature of the catalyzed cure reactions and (iii) the environmental sensitivity of the BF3 NH2CzH5 catalyst. DSC studies are also reported on the cure reaction characteristics and environmental sensitivity of commercial prepregs that contain BF3 amine catalysts. 

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