Nitroxide mediated polymerization of sustainably sourced isobornyl methacrylate and tridecyl methacrylate with acrylonitrile co‐monomer

Abstract

Nitroxide‐mediated polymerization (NMP) of isobornyl methacrylate (IBOMA) and tridecyl methacrylate (TDMA), derived from sustainable feedstocks, with a low fraction of acrylonitrile (AN) co‐monomer were conducted with unimolecular initiator BlocBuilder‐MA™ (BB) and the succinimidyl ester‐functionalized form, NHS‐BB. IBOMA and TDMA‐rich compositions were both polymerized at 100 °C in a controlled manner (i.e., linear increase in number average molecular weight [Mn] with conversion up to ∼40% and low dispersity, Đ < 1.5). SG1‐terminated poly(IBOMA‐stat‐AN) macroinitiator was then cleanly chain‐extended with poly(TDMA‐stat‐AN) and the diblock copolymers exhibited two distinct glass transition temperatures (Tgs), indicative of microphase separation. IBOMA/TDMA/AN terpolymers with different IBOMA/TDMA molar ratios were also synthesized where terpolymers with higher IBOMA content had higher apparent rate constants and higher Tgs. Moreover, chain growth was linear up to conversions of ∼60% and all Đs were 1.51 to 1.64. Finally, 2‐hydroxyethyl methacrylate (HEMA) was incorporated into the IBOMA/TDMA/AN system, resulting in statistical quadripolymers. The quadripolymer Tg decreased with increasing TDMA content and Mn ranged from 12 to 15.4 kg mol−1 and the Đ were 1.39 to 1.54, suggesting the successful incorporation of sustainably sourced monomers into quadripolymers with a broad range of tunable Tgs via NMP with additional functionalities from HEMA. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2422–2436

Nitroxide mediated miniemulsion polymerization of methacryloisobutyl POSS: Homopolymers and copolymers with alkyl methacrylates

“…The melting points in the range of −25 to −30°C corresponds to the incorporation of C13MA monomers and it becomes noticeable as the C13MA becomes the major component. [ 48,49,69 ] This lower bound with respect to T m is seen quite clearly for the compositions of F C13MA > 80%. The melting points at higher temperatures ( T m > 50°C) are indicative of incorporation of POSSMA into the copolymers, as the T m for poly(POSSMA) approaches nearly 100 o C. [ 24 ] The absence of T g for POSSMA homopolymers and copolymers with high‐molar ratios of POSSMA ( F POSSMA ≥ 0.88) is probably due to the rigidity of polymer chains and the decrease in segmental mobility caused by the POSS cages.…”

“…[ 45–47 ] NMP of C13MA in homogeneous toluene solution and dispersed aqueous emulsion has been studied earlier and the successful homopolymerization, copolymerization and chain‐extension of this monomer has been illustrated. [ 48,49 ] Herein, the statistical copolymerization of different ratios of POSSMA/C13MA was performed in miniemulsion to synthesize copolymers with a wide range of T g s.…”

Incorporation of methacryloisobutyl POSS in bio‐based copolymers by nitroxide mediated polymerization in organic solution and miniemulsion

“…Such a deviation from the theoretically predictied line could be due to the irreversible termination reactions as seen in our previous studies. 38,45 Further, in Figure 3(b), Đ increases with conversion for all the experiments initiated with BB in toluene. This is probably caused by disproportionation between propagating radicals and the nitroxide at high conversions as reported elsewhere for polymerizations SG1 alkoxyamines.…”

“…The copolymerization of IBOMA/C13MA was previously done in organic solvent (toluene) and in aqueous miniemulsion. 38,45 To study the effect of POSSMA on the miniemulsion polymerization of IBOMA/C13MA mixtures, terpolymerization of IBOMA/C13MA/POSSMA was conducted using similar reaction conditions at 90 C. For miniemulsion polymerization, the feed molar ratio of 1:1 was set for IBOMA/C13MA, while the [POSSMA] varied for in each experiment. Table 4 illustrates the experimental conditions for terpolymerization of IBOMA/C13MA/ POSSMA.…”

“…A similar result was observed for block copolymers of IBOMA/C13MA compared to their counterpart statistical copolymers. 45 The glass transition temperatures (T g s) were measured by DSC and are listed in Table 7. The addition of IBOMA (T g,p(IBOMA) = 110-200 C 27-30 depending on the chain length) and POSSMA (T g,p(POSSMA) = 85 C) 9 is expected to provide stiffness to the chains, while the long aliphatic chain in C13MA (T g,p(C13MA) = −46 C) is expected to provide enhanced flexibility.…”