Does the oxa-Michael reaction of 2-trifluoromethacrylic acid lead to fluorinated polyesters?. Issue 31 (23rd July 2021)

• Record Type: Journal Article
• Authors: Tran-Do, Minh-Loan; Eid, Nadim; Totée, Cédric; Gimello, Olinda; Améduri, Bruno
• Is Part Of: Polymer chemistry. Volume 12:Issue 31(2021)
• Page Start: 4508
• Page End: 4523
• Publication Date: 2021-07-23
• Subjects: Polymers -- Periodicals; Macromolecules -- Periodicals; Polymerization -- Periodicals; 547.705
• DOI: 10.1039/d1py00685a
• Languages: English
• ISSNs: 1759-9954

Abstract

Abstract : 2-Trifluoromethacrylic acid (MAF) is a peculiar fluorinated functional monomer. Abstract : 2-Trifluoromethacrylic acid (MAF) is a peculiar fluorinated functional monomer. Though it is known to polymerise via CC bond cleavage under anionic initiation, its oxa-Michael addition polymerisation afforded polyesters bearing trifluoromethyl side groups. This oxa-Michael addition was attempted in the presence of radical (peroxides), basic (amines and phosphines) and acidic (AlCl3, triflic acid, and p -toluenesulfonic acid) reactants and catalysts which led to the formation of oligomers with various yields (up to 57%) and molar masses (up to 2200 g mol −1 ). The obtained polyesters were characterised by GC/MS, IR, 19 F NMR, 1 H NMR and 13 C NMR spectroscopy techniques and MALDI-TOF, and their thermal properties were determined by thermogravimetric analysis and differential scanning calorimetry. Triphenylphosphine and piperidine led to the highest degree of polymerization DP n (up to the 16th adduct) with a degradation temperature of about 200 °C. The glass transition temperatures ( T g ) were −59 and −46 °C for the MAF bisadduct (diMAF) and oligoMAF, respectively. Such oligomers were hydrophobic, evidenced by a water contact angle measurement of 107°, showing that the contribution of the trifluoromethyl group was higher than that of the ester function.