Premium
Synthesis of hyperbranched polyphenylenes using aryl dichloride monomers by Suzuki polycondensation
Author(s) -
Lobo Laurel Simon,
Matsumoto Kazuya,
Mitsutoshi Jikei
Publication year - 2020
Publication title -
polymers for advanced technologies
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.61
H-Index - 90
eISSN - 1099-1581
pISSN - 1042-7147
DOI - 10.1002/pat.4914
Subject(s) - condensation polymer , monomer , materials science , polymer chemistry , thermal stability , polymer , solubility , chloride , branching (polymer chemistry) , polymerization , interfacial polymerization , organic chemistry , chemistry , composite material , metallurgy
Advanced microelectronic fabrication requires stable organic materials that can be used under extreme conditions such as high temperatures. In this study, hyperbranched polyphenylenes (HBPs) were synthesized as stable and soluble polymers via the Suzuki polycondensation of 2‐(3,5‐dichlorophenyl)‐4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolane (Bpin‐Cl) and 3,5‐dichlorophenylboronic acid (BOH‐Cl) in the presence of palladium acetate and 2‐(2′,6′‐dimethoxybiphenyl) dicyclohexylphosphine (SPhos). Soluble polymers having an average molecular weight in the range of 11 000 to 31 000 g/mol were obtained through the polymerization of chloride monomers. The degree of branching was determined to be 50% through inverse‐gated decoupling 13 C NMR measurements. The chloride‐terminated HBP showed a temperature of 402°C for 1% weight loss ( T d1% ) after the sample was purified via precipitation from an N ‐methyl‐2‐pyrrolidone (NMP) solution and then thermally treated at 260°C for 3 hours. This thermal stability is higher than that of the HBPs synthesized from the corresponding bromide monomers. Moreover, after heating at 260°C, the sample was found to be soluble in organic solvents. The chlorinated terminal groups played an important role in achieving good solubility after heating. This unique property is attractive for non‐volatile or temporary coating materials used in microelectronic fabrication.