Bio-based block polymers derived from lignin and fatty acids
The present invention pertains to bio-based block polymers synthesized from functionalized lignin-based molecules (A-monomer) and functionalized fatty acids or fatty alcohols (B-monomer) derived from plant or animal oils, waxes or fats. The block polymers can be synthesized via numerous polymerization techniques, such as reversible addition-fragmentation chain transfer (RAFT). Most importantly, this class of bio-based block polymers shows promise as providing sustainable yet scalable and tunable thermoplastic elastomers and pressure-sensitive adhesives, among other applications.
1. A block polymer comprising at least one A-block and at least one B-block, wherein the A-block contains a polymerized lignin-based monomer or polymerized combination of lignin-based monomers, wherein said lignin-based monomer or monomers have the general formula Ar—O—C(═O)—C(R)═CH 2 or Ar—O—C(═O)—C(R)═CHCO 2 H, where Ar is an aromatic residue obtained from a cresol, a xylenol, a guaiacol, a catechol, a syringol, a vanillin or a combination thereof, and R is H or CH 3 , and the B-block contains a polymerized fatty acid-based monomer, polymerized fatty alcohol-based monomer or a polymerized combination of fatty acid-based monomer(s) or fatty alcohol-based monomer(s).
2. The block copolymer of claim 1 , wherein Ar is obtained from an aromatic residue selected from the group consisting of o-cresol, m-cresol, p-cresol, 2,6-dimethylphenol, 2,4-dimethylphenol, guaiacol, 6-ethylguaiacol, 4-ethylguaiacol, 4-propylguaiacol, catechol, 6-methylcatechol, 4-methylcatechol, 6-ethylcatechol, 4-ethylcatechol, 3-methoxycatechol, syringol, and vanillin and combinations thereof.
3. A block polymer comprising at least one A-block and at least one B-block, wherein the A-block contains a polymerized lignin-based monomer or polymerized combination of lignin-based monomers, wherein said lignin-based monomer or monomers have the general formula Ar—O—C(═O)—C(R)═CH 2 , where Ar is an aromatic residue obtained from cresol, xylenol, guaiacol, catechol, syringol, vanillin and combinations thereof, and R is H or CH 3 , and the B-block contains a polymerized fatty acid-based monomer, polymerized fatty alcohol-based monomer or a polymerized combination of fatty acid-based monomer(s) or fatty alcohol-based monomer(s).
4. The block polymer of claim 1 , wherein the fatty acid-based monomer(s) or fatty alcohol-based monomer(s) contains at least one hydrocarbon chain of between 1 to 36 carbon atoms.
5. The block polymer of claim 1 , wherein the fatty acid-based monomer(s) or fatty alcohol-based monomer(s) contains at least one unsaturated carbon-carbon bond, not necessarily in a hydrocarbon chain, prior to polymerization.
6. The block polymer of claim 1 , wherein the fatty acid-based monomer(s) or fatty alcohol-based monomer(s) contains at least one chemical functionality selected from the group consisting of methacrylate, acrylate, maleic, allyl, alkenyl, hydroxyl, and epoxy moieties and combinations thereof, either prior to polymerization or post-polymerization.
7. The block polymer of claim 1 , wherein the fatty acid-based monomer(s) or fatty alcohol-based monomers) is derived from at least one of the following: propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid, arachidic acid, heneicosylic acid, behenic acid, tricosylic acid, lignoceric acid, pentacosylic acid, cerotic acid, heptacosylic acid, montanic acid, nonacosylic acid, melissic acid, henatriacontylic acid, laccoroic acid, psyllic acid, geddic acid, ceroplastic acid, hexatriacontylic acid, ricinoleic acid, the unsaturated analogues of these acids, the saturated and unsaturated alcohols analogous to these acids, and combinations thereof.
8. The block polymer of claim 1 , wherein the fatty acid-based monomer(s) or fatty alcohol-based monomer(s) is derived from a triglyceride(s).
9. The block polymer of claim 8 , wherein the triglyceride(s) is obtained from a plant or animal.
10. The block polymer of claim 8 , wherein the triglyceride(s) is obtained from a plant or animal oil, wax, or fat.
11. The block polymer of claim 1 , wherein the block polymer is an A-B block copolymer, an A-B-A block copolymer, an A-B-B-A block copolymer, a B-A-B block copolymer, a B-A-A-B block copolymer, an A-B-A-B block copolymer, a B-A-B-A block copolymer, an A-B-A-B-A block copolymer, or a B-A-B-A-B block copolymer.
12. The block polymer of claim 1 , wherein the B-block contains a methacrylate-functionalized fatty alcohol.
13. The block polymer of claim 12 , wherein the methacrylate-functionalized fatty alcohol has the general structure H 3 C(CH 2 ) x OC(═O)C(CH 3 )═CH 2 where x is an integer from 2 to 24.
14. The block polymer of claim 12 , wherein the (meth)acrylate-functionalized fatty alcohol is lauryl methacrylate.
15. The block polymer of claim 1 , wherein the fatty acid-based monomer, fatty alcohol-based monomer or combination of fatty acid-based monomer(s) or fatty alcohol-based monomer(s) include at least one of a monomer derived from butyric acid, a monomer derived from a saturated or unsaturated alcohol analogous to butyric acid, a monomer derived from lauric acid, or a saturated or unsaturated alcohol analogous to lauric acid.