Terminal silanol groups on the glass surface were used for the chemical bonding of α-bromo amide as the initiator for surface initiated Cu(0)-mediated living radical polymerization (LRP) to graft well-defined poly(butyl arylate) (PBA) and poly(2,2,2-trifluoroethyl methacrylate) (PTFEM) brushes on the glass surface. A grafting to methodology was also performed by the modification of the glass surface using a thiosilane agent and performing a thio-bromo click reaction in the presence of PBA and PTFEM synthesized via Cu(0)-mediated LRP. Furthermore, a one-pot grafting to method was developed that proved a facile, fast, and efficient method for grafting a bromo-terminated polymer to the glass surface in one step. All glass slides were characterized using ATR-FTIR and UV-vis spectroscopy, water contact angle measurements and SEM. The surface topology and roughness of selected samples were analyzed using AFM. Results show that an ultrathin layer of a polymer with nanoscale features and high roughness was chemically grafted to the glass surface without compromising glass transparency. These methodologies can be used to graft well-defined polymers with different functionalities on the glass surface.
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A green solvent-to-polymer upgrading approach to water-soluble LCST poly( N -substituted lactamide acrylate)s
We report a green solvent-to-polymer upgrading transformation of chemicals of the lactic acid portfolio into water-soluble lower critical solution temperature (LCST)-type acrylic polymers. Aqueous Cu(0)-mediated living radical polymerization (SET-LRP) was utilized for the rapid synthesis of N -substituted lactamide-type homo and random acrylic copolymers under mild conditions. A particularly unique aspect of this work is that the water-soluble monomers and the SET-LRP initiator used to produce the corresponding polymers were synthesized from biorenewable and non-toxic solvents, namely natural ethyl lactate and BASF's Agnique® AMD 3L ( N , N -dimethyl lactamide, DML). The pre-disproportionation of Cu( i )Br in the presence of tris[2-(dimethylamino)ethyl]amine (Me 6 TREN) in water generated nascent Cu(0) and Cu( ii ) complexes that facilitated the fast polymerization of N -tetrahydrofurfuryl lactamide and N , N -dimethyl lactamide acrylate monomers (THFLA and DMLA, respectively) up to near-quantitative conversion with excellent control over molecular weight (5000 < M n < 83 000) and dispersity (1.05 < Đ < 1.16). Interestingly, poly(THFLA) showed a degree of polymerization and concentration dependent LCST behavior, which can be fine-tuned ( T cp = 12–62 °C) through random copolymerization with the more hydrophilic DMLA monomer. Finally, covalent cross-linking of these polymers resulted in a new family of thermo-responsive hydrogels with excellent biocompatibility and tunable swelling and LCST transition. These illustrate the versatility of these neoteric green polymers in the preparation of smart and biocompatible soft materials.
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- NSF-PAR ID:
- 10401791
- Date Published:
- Journal Name:
- Green Chemistry
- Volume:
- 24
- Issue:
- 21
- ISSN:
- 1463-9262
- Page Range / eLocation ID:
- 8314 to 8323
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2GC02780A
