𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Synthesis and characterization of A2 + B3-type hyperbranched aromatic polyesters with phenolic end groups

✍ Scribed by Zhirong Fan; Albena Lederer; Brigitte Voit

Publisher
Elsevier Science
Year
2009
Tongue
English
Weight
288 KB
Volume
50
Category
Article
ISSN
0032-3861

No coin nor oath required. For personal study only.

✦ Synopsis

Hyperbranched (hb) aromatic polyesters with phenolic end groups were synthesized according to the A 2 þ B 3 approach both, by solution polymerization and by melt (bulk) polymerization with different monomer ratios (A 2 :B 3 ). The hb polyesters produced from solution polymerization exhibited higher yields, molar masses and glass transition temperature (T g ) compared to the products prepared in the melt. The resulting hb aromatic polyesters from the A 2 þ B 3 approach were also compared with their properties to hb aromatic polymers produced from the well known AB 2 monomer 3,5-bis-(trimethylsiloxy)benzoyl chloride. Both types of hb aromatic polyesters possess high T g , high thermal stability and good solubility in common organic solvents. A typical melt viscosity behavior with shear thinning effect was also observed for both. Thus similar polymer properties compared to melt-condensed products were obtained with the A 2 þ B 3 approach by solution polycondensation possessing the advantage of easy monomer availability and much milder polymerization conditions (at room temperature in solution) compared to the AB 2 approach.

📜 SIMILAR VOLUMES

Synthesis and structural features of UVI
Synthesis and structural features of UVI and VIV chelate complexes with (hhmmbH)Cl·H2O [hhmmb = {3-hydroxyl-5-(hydroxymethyl)-2-methylpyridine-4-yl-methylene}benzohydrazide], a new Schiff base ligand derived from vitamin B6
✍ Davi Fernando Back; Marco Aurélio Ballin; Gelson Manzoni de Oliveira 📂 Article 📅 2009 🏛 Elsevier Science 🌐 English ⚖ 480 KB

The Schiff base ligand {3-hydroxyl-5-(hydroxymethyl)-2-methylpyridine-4-yl-methylene}benzohydrazide hydrochloride monohydrated {(hhmmbH)ClÁH 2 O} (1) was prepared by reaction of pyridoxine hydrochloride with benzoic acid hydrazide. The reaction of 1 with [VO(acac) 2 ] and triethylamine yields the ne

Structural characterization of [(μ-H)Os3
Structural characterization of [(μ-H)Os3(CO)10(μ-NH2)] and a new polymorphic form of [(μ-H)Os3(CO)10(μ-SH)]. Influence of the bridging group on the geometry of compounds [(μ-H)Os3(CO)10(μ-X)] (X = NH2, NRH, PRH, SbR2, OH, SH, SR, SeR, Cl, Br). Reactions of [(μ-H)Os3(CO)10(μ-X)] (X = OH and SH) with proton sponge
✍ Ottmar R. Reyes-López; Marco A. Leyva; María J. Rosales-Hoz 📂 Article 📅 2011 🏛 Elsevier Science 🌐 English ⚖ 331 KB
In situ synthesis, structural characteri
In situ synthesis, structural characterization and luminescent property of a novel hybrid solid with twofold interpenetrating (4,6)-connected topology [{(Cu4I4)2H2O}{Cu6(mtz)6}]n (Hmtz = 3,5-dimethyl-1,2,4-triazole)
✍ Yunlong Fu; Hui Lu 📂 Article 📅 2008 🏛 Elsevier Science 🌐 English ⚖ 382 KB

A novel three-dimensional hybrid solid, [{(Cu 4 I 4 ) 2 H 2 O}{Cu 6 (mtz) 6 }] n (1) (Hmtz = 3,5-dimethyl-1,2,4-triazole), was synthesized under solvothermal condition. The structure of 1 consists of four-connected Cu 4 I 4 clusters and hexanuclear Cu 6 (mtz) 6 rings as secondary building units (SBU