Methyl methacrylate based copolymers and terpolymers: Preparation, identification, and plasticizing capability for a poly(methyl methacrylate) used in aviation

Abstract

In this study, we first synthesized transparent poly(methyl methacrylate–maleic anhydride) [P(MMA–MAH)] and poly(methyl methacrylate–maleic anhydride–N‐2‐methyl‐4‐nitrophenyl maleimide) [P(MMA–MAH–MI)] via free‐radical polymerization at different monomer ratios. The synthesized polymers were characterized by titration, viscometric, spectroscopy, and thermal analyses. Higher contents of maleic anhydride (MAH) resulted in increases in the viscosity, glass‐transition temperature (Tg), and transparency. The synthesized polymers were then blended with a commercial‐grade poly(methyl methacrylate) (PMMA) used in aviation in the presence of CHCl3. According to the free volume theory, the incorporation of 5 wt % P(MMA–MAH)s or P(MMA–MAH–MI)s into the commercial PMMA resulted in a plasticizing impact on this thermoplastic, which was confirmed by the decrease in the Tg values of the blends with almost the same transparency as the initial PMMA. In fact, the higher the content of MAH was, the lower the Tg of the blends was. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46603.

Crosslinked poly(methyl methacrylate) with perfluorocyclobutyl aryl ether moiety as crosslinking unit: thermally stable polymer with high glass transition temperature

“…3A). Moreover, the existence of TFVE group appeared at À119.2, À126.1 and À134.0 ppm in 19 F NMR spectrum (Fig. 4B) further conrmed the preservation of TFVE groups in PTFVOPMA-co-PMMA copolymer.…”

“…1 H, 13 C and 19 F NMR spectra of intermediates were recorded on a JEOL resonance ECZ 400S spectrometer (400 MHz) in CDCl 3 . Tetramethylsilane (TMS) and CDCl 3 were used as internal standards for 1 H and 13 C NMR, respectively; CF 3 CO 2 H was used as an external standard for 19 F NMR. FT-IR spectra were recorded on a Nicolet AVATAR-360 FT-IR spectrophotometer with a resolution of 4 cm À1 .…”

“…The weight of the lms was weighed immediately. 19 F NMR. The characteristic peaks of double bond are found to be located at 5.75 ('b') and 6.31 ('c') ppm in 1 H NMR spectrum of TFVOPMA (Fig.…”

“…The proton resonance signal of methyl linked to the double bond appears at 2.03 ppm ('a'), while the resonance signals at 7.17 ('d') and 7.23 ppm ('e') belong to phenyl protons. In 19 F NMR spectrum of TFVOPMA (Fig. 1B), characteristic peaks of -OCF] CF 2 group appear at À120.3, À127.8 and À135.3 ppm, respectively.…”

“…Wilkie et al prepared MMA-DVB crosslinked polymers using divinylbenzene (DVB) as crosslinking agents and the degradation temperature (T d,5% ) of resulting polymers increased from 162 C to 294 C. 12 Kuo et al suggested an approach to raise the T g of PMMA through copolymerization with methacrylamide (MAAM) since hydrogen-bonding interactions exist between these two monomer segments. [16][17][18][19] Fluoropolymers have attracted much curiosity in material science due to their unique properties including thermal stability, chemical resistance, ame retardancy, superior electrical insulating ability, low dielectric constant and refractive index, and unique surface property. [20][21][22] To avoid low processability of peruoropolymers, partially-uorinated polymers like poly(vinylidene uoride) (PVDF), 4,5 alternating ethylene-tetrauoroethylene (ETFE) 23 and alternating ethylene-chlorotriuoroethylene (ECTFE) copolymers, 24,25 have been prepared and exhibited improved processability.…”