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Polymer nanoparticles are an emerging class of materials with potential impact in sensing, catalysis, imaging, cosmetics, and therapeutics. Here, a collection of graft polymers with conjugated polythiophene backbones were synthesized via a grafting-to approach. We functionalized polythiophene backbones with side chains of either poly(3-hexylthiophene) (P3HT), poly(ethylene oxide), or poly(methyl methacrylate) (PMMA) via copper-catalyzed azide–alkyne click chemistry. The backbones, graft polymers and a linear poly(3-hexylthiophene) were fabricated into nanoparticles through precipitation in aqueous media. We measured the absorption and emission spectra of the polymers dissolved in chloroform and as nanoparticles suspended in water. Compared to linear P3HT, all graft polymer nanoparticles exhibit higher quantum yields. Moreover, the addition of PMMA side chains increased the quantum yield by more than two orders of magnitude. This versatile approach to conjugated graft copolymer synthesis demonstrates a route for enhancing photoluminescence of conjugated polymer nanoparticles that could be beneficial for a variety of applications, such as biosensing and bioimaging.
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This content will become publicly available on October 13, 2026
Well-Defined Amylose Acetate- graft -polylactide Graft Polymers as Compatibilizers for Renewable Polymer Blends
Regioselectively substituted amylose acetate-graft-polylactide (AmAc-g-PLA) graft copolymers were synthesized via grafting-to “click” reaction between C6-azide functionalized AmAc and alkyne-terminated PLA. Alkyne-terminated PLA synthesized through organocatalytic ring-opening polymerization (ROP) permitted control over graft degree of polymerization (DP) and stereochemistry, while azide functionalized AmAc with tailorable C6-azide degree of substitution (DS) allowed graft density control. This describes the first synthesis of polysaccharide-based graft copolymers with exclusive C6 grafting and controllable topology. Thermal analysis indicates glass transition temperatures (Tg) of AmAc and PLA segments are affected after grafting-to coupling, with poly(L-lactide) (PLLA) grafts maintaining crystallizability. AmAc-graft-poly(D,L-lactide) (PDLLA) graft polymers were effective compatibilizers for immiscible blends of starch acetate (StAc) and PDLLA as evidenced by small-angle laser light scattering (SALLS) and phase contrast optical microscopy (PCOM). This method permits determination of structure-property relationships with regard to the effect of graft polymer topology on blend compatibilization, which will be the focus of a future study.
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- PAR ID:
- 10681341
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Biomacromolecules
- Volume:
- 26
- Issue:
- 10
- ISSN:
- 1525-7797
- Page Range / eLocation ID:
- 6893 to 6905
- Subject(s) / Keyword(s):
- regioselectivity, carbohydrates, ring-opening polymerization, phase separation, biodegradable
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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