1,3-Bis(2-pyrryl)benzene was used to prepare dibenziamethyrin, in which two pyrrole units of [24]amethyrin(1.0.0.1.0.0) are replaced by benzene. 1,4-Bis(2-pyrryl)benzene, 2,5-bis(2-pyrryl)thiophene, and 4,4'-bis(2-pyrryl)biphenyl were also used in place of 2,2'-bipyrrole to give expanded analogues of [24]rosarin(1.0.1.0.1.0) and [32]octaphyrin(1.0.1.0.1.0.1.0). These large porphyrinoids can incorporate multiple metal units of Rh(CO)2 and Pd(π-allyl) with considerable deviation of the metal atoms from the dipyrrin planes, evidenced by X-ray crystallography. The coordinated Rh(CO)2 group shuttled between both sides of the macrocycle; the rate was dependent on the spacer, ring size, and number of metal atoms. Variable temperature (1) H NMR spectroscopy showed that the tris-rhodium complexes of the expanded rosarins with 1,4-phenylene or 2,5-thienylene spacers adopt a C3v -symmetric form and a Cs -symmetric form as a result of the Rh(CO)2 groups hopping through the macrocycle cavity. The C3v -symmetric form has a greater dipole moment and, therefore, is favored in solvents of greater polarity. The Rh(CO)2 groups in the tris-rhodium complex of the expanded rosarin with 4,4'-biphenylene spacers hop so fast that an averaged spectral pattern (D3h ) was seen in the (1) H NMR spectrum, even at -60 °C. Expanded octaphyrins with 1,4-phenylene and 2,5-thienylene spacers bind four Rh(CO)2 groups outside the macrocycle cavity to form a D2d -symmetric saddle-shaped structure that did not show any dynamic behavior on the NMR timescale, even at 80 °C. This tetranuclear complex is one of the largest porphyrinoid metal complexes characterized by X-ray crystallography to date.

Adhesion and viscoelastic properties and morphology of a polyacrylic block copolymer/tackifier blend were investigated. Special rosin ester resins with different weight average molecular weights of 650, 710, 890, and 2160 were used as the tackifier and blended with a polyacrylic block copolymer consisting of poly(methyl methacrylate) and poly(n-butyl acrylate) blocks at tackifier content levels of 10, 30, and 50 wt %. The compatibility decreased with an increase in molecular weight. From TEM observation, the number of formed agglomerates of the tackifier with sizes on the order of several tens of nanometers increased with increasing tackifier content and molecular weight of the tackifier in the range from 650 to 890. For the tackifier with a molecular weight of 2160, micrometer-sized agglomerates were observed. The storage modulus at low temperature and the glass transition temperature of adhesive measured by a dynamic mechanical analysis increased dependent on the number of formed nanometer sized agglomerates. Tack was measured using a rolling cylinder tack tester over wide temperature and rolling rate ranges, and master curves were prepared in accordance with the time-temperature superposition law. Tack and peel strength were optimum at a blend combination of intermediate compatibility, i.e., the molecular weight of 890. These optimum properties were correlated to maximal values of the storage modulus at room temperature and the glass transition temperature. Therefore, it was found that these features of blend properties are strongly affected by the nanometer sized agglomerates of tackifier.

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