United States Rubber Co., Inc.

A review with 32 referencesThe thianthrene cation radical (Th^·+) undergoes electron transfer in reactions with azoalkanes.The oxidized azoalkanes then enter primarily into carbocation reaction pathways rather than the free radical pathways with which they are commonly associatedReactions of Th^·+ with Grignard agents also result in electron transfer from the Grignard to Th^·+.Here again carbocation chem. is seen but particularly with THF as solvent, which polymerizes.The Grignard group may end up primarily as alkane or may also be trapped by Th^·+ in the form of a 5-alkylthianthreniumyl ion.Possible mechanisms of reactions are discussed.

We have presented a method for evaluating the vacuum forming performance of polymers by comparing their forming window. The window is determined by (a) the sag of the heated sheet and (b) the material's ability to reproduce mold details. We also showed that the vacuum forming window of polypropylene homopolymer can be widened through modification with an olefinic thermoplastic elastomer. Compared to polypropylene homopolymer, TPE-modified polypropylene requires lower tensile stress to extend the sample at temperatures below the polypropylene melting point. In the melt stage. TPE modification enhances the melt viscosity of polypropylene. TPE modification increases significantly the low temperature impact of polypropylene. The flexural modulus becomes lower.

Alkylation and halogenation of sulfones proceed smoothly using NaOH in DMF.E.g., alkylation of RCH₂SO₂R¹ (I; R = 2,5-Me₂C₆H₃, R¹ = 1-oxopyrid-2-yl) with R²Cl (R² = Me, CH₂:CHCH₂) in NaOH/DMF gave 74-92% RCHR²SO₂R¹ (R-R² as before), whereas halogenation of I (R = naphth-2-yl, R¹ as before) with CCl₄ in NaOH/DMF gave 96% RCHClSO₂R¹ (R, R¹ as before).In addition, both halogenation and alkylation can be performed in the same flask to obtain α-disubstituted products.Thus, PhCH₂SO₂R (R = 1-oxopyrid-2-yl) underwent sequential treatment with CCl₄ and MeI in NaOH/DMF to give 77% PhCClMeSO₂R (R as before).