Synthesis of methacrylate polymer bearing cyanate groups and its chemoselective reaction with amines

Abstract

A novel reactive polymer containing cyanate groups in the side chain was prepared by free radical polymerization of a cyanate‐containing monomer, 2‐(4‐cyanatophenyl)ethyl methacrylate (1). The monomer 1 and its polymer, poly[2‐(4‐cyanatophenyl)ethyl methacrylate] (PCPMA), were stable under the air for a long period. The copolymerization of 1 and methyl methacrylate provided the corresponding copolymers with various cyanate contents. The availability of the cyanate‐containing polymers as a reactive polymer was investigated. Model reaction using 4‐cyanatotoluene revealed that a cyanate group reacted with aliphatic amines, whereas no reaction occurred in the presence of water, alcohols, and aromatic amines under mild conditions. Post‐functionalization of PCPMA was demonstrated using aliphatic amines or diamines. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 699–706

Origin of the Rapid Trimerization of Cyanate Ester in a Benzoxazine/Cyanate Ester Blend

“…The exothermic peak temperature decreased with increasing amount of N,Ndimethylaniline, while the exothermic enthalpy increased with More recently, Endo et al reported that triphenylphosphine reacts with cyanate ester, and forms phosphonium salt according to 1 H NMR analysis. 30 The reaction occurs through the nucleophilic addition of unpaired electrons of triphenylphosphine on the electron-deficient cyanate ester (see Scheme 3 of the above study 30 ). Based on Endo's result along with the IR and DSC analyses mentioned above, we propose a threestep catalytic mechanism of benzoxazine for the trimerization of cyanate ester in Scheme 2.…”

“…Through IR and DSC analyses, we conclude that the tertiary amine of benzoxazine catalyzes the trimerization of cyanate ester. Based on Endo's result 30 along with the IR and DSC analyses mentioned above, we propose a three-step catalytic mechanism of benzoxazine for the trimerization of cyanate ester in Scheme 2. Indeed, the phenolic OH 23,24 and the oxygen anion 28 also catalyze the trimerization of cyanate ester, but the catalysis occurs after the ring-opening polymerization of benzoxazine.…”

Crosslinking and ozone degradation of thermosetting resins based on maleic anhydride/diene copolymer and polyfunctional alcohols

“…The quantitative ring‐opening reaction of the anhydride groups required the harder reaction conditions, such as reflux in toluene for 5 h. The peak due to the anhydride moiety was not observed in the spectrum of the isolated product [Figure (c)]. In the literature, the reactivity of functional groups, such as anhydride, acyl chloride, and isocyanate groups, was reduced when they were incorporated as a part of the polymer repeating structure …”

“…In the literature, the reactivity of functional groups, such as anhydride, acyl chloride, and isocyanate groups, was reduced when they were incorporated as a part of the polymer repeating structure. [25][26][27][28][29][30]…”

Investigation of the hardener with latent and rapid curing based on phenol‐amine salts for applications to cyanate ester resins

“…The Infrared spectroscopic (IR) spectrum of pCr‐DPEA in the solid state below 76°C strongly suggests that the ion dissociated state is preferred, and the hydrogen bonding state dominates in the molten state at 80°C (SI). On the other side, regarding the reactions of phenols or amines with the cyanate ester, cyanate esters does not only react with weakly acidic phenols 19 to form the triazine via an intermediate imino carbonate, but with nucleophilic amines rapidly to give cyanate‐amine adducts or triazines substituted with amino groups 20–22 . In the case of the addition of equal amounts of aromatic amines and phenols to cyanate esters, it has been found out that the products contain the imino carbonates and the cyanate‐amine adducts in the ratio of 1:2.…”