No abstract

Hyperbranched polysiloxysilane (HBPS) with terminal vinyl groups P1 was synthesized by self-condensation reaction using platinum-catalyzed hydrosilylation of 1,1,3,5,5-pentamethyl-1,5-divinyltrisiloxane. A number-average molecular weight (M n ) was 5400 with a polydispersity index of 1.49. End-functionalization of the terminal vinyl groups was carried out by epoxidation with 3-chloroperoxybenzoic acid to afford epoxy-terminated HBPS P2. The polymers obtained were characterized by IR, 1 H, 13 C, 29 Si NMR spectroscopy. The degree of branching of HBPS was estimated as 0.57 in comparison of 29 Si NMR spectra of P2 and model compounds. The glass transition temperatures (T g ) of P1 and P2 were observed at À97 C and À77 C, respectively. The 10% weight loss temperatures (T 10 ) of P1 and P2 were over 440 C in nitrogen.KEY WORDS: Hyperbranched Polymer / Polysiloxysilane / End-functionalization / Epoxidation / Degree of Branching / Developing siloxane-based organic-inorganic hybrid polymers has attracted much attention in studies on interfaces of various organic/inorganic materials because of their unique properties such as adhesion, excellent thermal and oxidative stability, lubricity, high flexibility, and biocompatibility.

Solvent free oxidative coupling reaction of 3HT within a nanocavity is demonstrated. The side reaction at the 4-position is regulated.

The local mechanical properties of crystalline polymer were evaluated using synchrotron radiation X-ray diffraction with 10 μm lateral resolution. A nonoriented isotactic polypropylene (iPP) film with isolated spherulites in a crystallized matrix was used as a model sample. In situ wide-angle X-ray diffraction (WAXD) measurement was performed on the iPP film using a microbeam synchrotron radiation X-ray under sinusoidal strain. The lattice spacing of the crystal planes increased and decreased in response to the applied sinusoidal strain. Local dynamic viscoelastic functions (dynamic storage and loss moduli ( E′ and E″)) were calculated at room temperature from the relationship between the calculated applied stress and the response strain obtained by dynamic μ-beam WAXD measurement inside and outside of the spherulites. The E′ values inside and outside of spherulite obtained from the change in spacing of the (110) plane were 1.8 and 1.1 GPa, respectively. Furthermore, the E′ value inside of spherulite obtained from the change in spacing of the (1̅13) plane was 6.0 GPa. These values can be explained by the deformation of crystallite, which depends on the direction of crystal planes. The results obtained here revealed that synchrotron radiation X-ray diffraction measurement gives not only structural information but also the local mechanical properties of the materials E′.

A series of polyamide dendrimers (GO-G2) having carboxy1 groups on the periphery were prepared by the divergent method. The reaction of G 18NH2 dendrimer with glutaric acid anhydride gave polyamide dendrimer (Gi-8COOH). The structure of polyamide dendrimers were confirmed by IR, 1H, 13C NMR, MALDI-TOF mass, and elemental analysis. Poly(4-vinylpyridine) (P4VP) was prepared by atom transfer radical polymerization of 4-vinylpyridine. A hydrogen bonded GI-8COOH/P4VP 1/8 (molar ratio) complex was prepared by mixing GIA8COOH with P4VP in methanol, followed by removing the solvent. IR spectrum of Gl-8COOH/P4VP 1/8 complex showed the characteristic absorptions at 2550 and 1950 cm-1 due to the hydrogen bonding. A glass transition temperature (Tg) of GI-8COOH/P4VP 1/8 complex was observed at 177°C by DSC measurement, whereas the Tg values of G 1-8COOH and P4VP were at 147 and 138°C, respectively.