Lignin-Inspired Polymers with High Glass Transition Temperature and Solvent Resistance from 4-Hydroxybenzonitrile, Vanillonitrile, and Syringonitrile Methacrylates

Abstract

We here report on the synthesis and polymerization of nitrile-containing methacrylate monomers, prepared via straightforward nitrilation of the corresponding lignin-inspired aldehyde. The polymethacrylates reached exceptionally high glass transition temperatures ( T g values), i.e., 150, 164, and 238 °C for the 4-hydroxybenzonitrile, vanillonitrile, and syringonitrile derivatives, respectively, and were thermally stable up to above 300 °C. Copolymerizations of the nitrile monomers with styrene and methyl methacrylate, respectively, gave potentially melt processable materials with tunable T g values and enhanced solvent resistance. The use of lignin-derived nitrile-containing monomers represents an efficient strategy toward well-defined biobased high T g polymer materials.

Mechanosynthesis and Polymerization of Biosourced Styrene Derivatives Based on Building Blocks of Lignin

“…In this context, lignin, the second most abundant natural polymeric constituent of wood, accounting for around 20% of the lignocellulosic biomass and currently discarded as waste by the paper industry, appears to be a suitable candidate. Indeed, the controlled degradation of lignin allows to produce biofuels, precursors for organic synthesis, or oligomers that can be applied to prepare functional materials. , Among those examples, the compounds obtained from lignin degradation represent a promising alternative to design biosourced polymers displaying interesting thermomechanical properties ,− thanks to the presence of aromatic cycles. Besides, we have recently shown that lignin derivatives, based on guaiacyl or hydroxyphenyl units, could lead to polystyrene-type materials using the reversible addition–fragmentation chain transfer (RAFT) radical polymerization …”

“…Separation of those products is challenging, but progresses in this field have been recently reported. , The aforementioned phenolic aldehydes drawn from lignin have therefore been considered for polymerization. The main strategy encountered in the literature resides on the synthesis of acrylate esters on the phenol group for further polymerization. − The remaining aldehyde group offers in this case a possibility to functionalize the monomer. ,, Another way consists of converting them into styrene derivatives by changing the aldehyde of V , H , and S derivatives or conjugated carboxylic acid of ferulic acid derivatives into vinyl groups. Following this transformation, phenol moieties need to be protected, usually through an esterification reaction before radical polymerization can occur, as shown in our recent paper, followed, if needed, by a deprotection step. , Such a protection–deprotection sequence is efficient to produce polystyrenes with good thermal properties but is energy- and solvent-consuming.…”

Upcycling Waste Polycarbonate to Poly(carbonate imine) Vitrimers with High Thermal Properties and Unprecedented Hydrolytic Stability

“…Recycling of waste polymers has been extensively reported for sustainability. − Also, the use of biobased monomers − in the synthesis of high-performance thermoplastics, − thermosets, − vitrimers, − and other polymers , has been extensively reported and reviewed by Zeng et al and Rana et al Among several biobased monomers, vanillin is readily accessible because it holds two active functional groups (hydroxyl and aldehyde) at the para position of phenylene. Thermosets, due to their highly cross-linked structures, are not easy to recycle as they cannot be melted and reprocessed.…”

High-Performance Stimulus-Healable Sustainable Multiblock Copolymer Elastomers with Magnetothermal and Photothermal Properties

“…Natural resources, such as cellulose, lignin, starch, chitin, plant oils, and terpenes, have been utilized as promising candidates to fabricate novel biobased elastomers. − Lignin, the most abundant aromatic biopolymer, has been considered an ideal filler to design composite elastomers with improved properties . Alternatively, various aromatic-containing platform chemicals can be obtained by the depolymerization of lignin, and these lignin-derived aromatic compounds have been reported to produce high-value sustainable plastics, thermosets, and elastomers in order to fully substitute or partially replace the fossil-based polymers. − Vanillin, which can be transformed from lignin, is a representative lignin-based derivative that can be utilized to synthesize biobased polymer materials with high glass transition temperatures ( T g s) through controlled radical polymerization techniques. − The major challenge for biobased elastomers is their limited mechanical performance compared to those of fossil-based elastomeric materials. Therefore, it is of great importance and necessary to construct novel sustainable elastomers with significantly enhanced properties through topological architecture and network structure design.…”

“…Vanillin acrylate (VA) was synthesized according to the literature. 29 The chain transfer agent, S,S′-bis(α,α′-dimethyl-α″-acetic acid)trithiocarbonate (BDAT), was prepared as reported earlier. 48 Other commercial analytical reagents were used without further purification.…”