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New types of radical photoinitiators, based on azido and diazido structures, were compared to the reactivity of pure xanthone by using a photocalorimetry technique. Our results show that these photoinitiators are good candidates for radical polymerization.

We extend our previous formulation of low-energy QCD in terms of an effective lagrangean containing operators of dimensionality d ≤ 6 constructed with pseudoscalars and quark fields, describing physics below the scale of chiral symmetry breaking. We include in this paper the vector and axial-vector channels. We follow closely the Extended Chiral Quark Model approach and consistently work in the large-N c and leading log approximation and take into account the constraints from chiral symmetry and chiral symmetry restoration. The optimal fit of all parameters gives further support to a heavy scalar meson with a mass ∼ 1 GeV and a value of the axial pion-quark coupling constant g A 0.55 to 0.66, depending on some assumptions concerning the Weinberg sum rules.

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Thermal behavior of poly(vinyl alcohol)‐graft‐polyacrylamide copolymers (PVA‐g‐PAA), so‐called intramolecular polymer‐polymer complexes (intraPC), with variable M̄ vPAA and constant average number N of grafts is considered in this report. Complete compatibility of PVA and PAA through hydrogen bonding is realized in the range of the graft lengths not exceeding some critical value. The content of adsorbed and trapped water in graft copolymers reflects some features of PVA‐g‐PAAN structure depending on the graft lengths. The first thermal decomposition region in air for copolymers begins at higher temperatures with growing M̄ vPAA, but the total destruction interval reduces. Formal kinetic decomposition parameters of the first decomposition stage appear to be the largest for the PVA‐g‐PAA with the largest quantity of H‐bonds between the main and graft chains. Chemical transformations in graft copolymers, PVA and PAA during thermal decomposition are discussed.