The effects of the steric environment of the epoxy group on the curing and other properties of epoxy resins containing 3-oxatricyclo[3,2,1,0~~4]oct-6-yl and 4-oxatetracyclo[6,2,-1,02.~.03,5]undec-9(or 10)-yl residues have been examined: During the anhydride cure of certain members of the former class, an evolution of gas was observed. This is attributed to intramolecular reaction between the epoxide group and the linkage between the two ring systems. Stereoselectivity in epoxidation of tricyclo [5,2,1,02*6]undec-3-en-8(or 9)-yl derivatives is high, and the two possible series of stereoisomers have been obtained, by epoxidation with peracetic acid and by formation and saponification-dehydrochlorination of chlorohydrin-acetates, respectively. The relative reactivities of the two stereoisomeric series were examined. The route via the chlorohydrin is not applicable to epoxidation of dehydronorbornyl derivatives, owing to the occurrence of rearrangements.No analogous stereochemical effects were observed with cyclohexane-based epoxy resins. ZUSAMMENFASSUNG:Der EiduB der sterischen Anordnung der Epoxydgruppe auf den Hiirtungsverlauf und auf andere Eigenschaften von Epoxydharzen, die 3-Oxatricyclo [3,2,1,02~4]oct-(6)-yl-oder 4-0xatetracyclo[6,2,1,02~7,03~5]~ndec-(9 oder 10)-yl-reste enthalten, wurde untersucht. Die Gasbildung, die wahrend der Hartung gewisser Verbindungen der erstgenannten Klasse mit Anhydriden beobachtet wurde, ist durch eine intramolekulare Reaktion der Epoxydgruppe mit der Briickengruppe zwischen den cyclischen Resten erklarbar. Die Epoxydierung der Tricycl0[5,2,1,0~*~]undec-(3)-en-(8 oder g)-yl-Derivate ist durch eine starke Stereoselektivitat gekennzeichnet, und die beiden moglichen sterischen Isomertypen wurden einerseits durch Epoxydierung mit Peressigsaure und andererseits durch Bildung der Chlorohydrin-Acetate und ihre Verseifung und Dehydrochlorierung erhalten. Die relative Reaktivitat der beiden stereo-isomeren Reihen wurde untersucht. Das Chlorhydrinverfahren lafit sich wegen der dabei auftretenden Umlagerungsreaktionen nicht fiir die Epoxydierung von Bicyclo[2,2,l]hept-(5)-en-(2)-yl-derivaten anwenden. Bei Epoxydharzen, die auf der Basis des Cyclohexanrings aufgebaut sind, wurden keine analogen stereochemischen Erscheinungen beobachtet.

A new procedure for the glycidylation of aromatic amines has been developed recently, which leads to resins of lower viscosity, longer shelf‐life and higher purity than methods used previously. Resins made by the new process show considerable processing and applications advantages over those made by earlier methods. The new process has also made accessible high purity glycidyl derivatives of amines which have hitherto proved difficult to glycidylate effectively.

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Several types of polythiol resin were applied to wool fabric from organic solvent or aqueous emulsion and cured at room temperature to give shrink resistance. The most successful polythiols were those containing polyether structures and thiol functionality greater than two. Reaction of one of these polythiols with oxygen gas was demonstrated and is believed to be the means whereby the polythiols cure on the wool surface, forming disulfide crosslinks. Organic and inorganic bases, organic peroxides and hydroperoxides, and heavy metal compounds were effective catalysts. The influence of structural differences in the polythiols on the shrink resistance is discussed.

Compounds of the types [π‐C5H5M(CO)nX] (M = Fe, n = 2; M = Mo, n = 3; X = CH3, CH2C6H5, CH2Si(CH3)3, CH2OCH3, Sn(C6H5)3, SnCl3, HgCl, I), [Mn(CO)5CH3], and [(π‐CH3C5H4)Mn(CO)3] have been examined as catalysts for the cure of epoxy resins under various conditions. It was found that the compounds [π‐C5H5Fe(CO)2R] (R = CH3, CH2C6H5) and [π‐C5H5Mo(CO)3CH3] are active photosensitizing agents for the anhydride cure of certain epoxy resins. The mechanism of the process is discussed.