Stimuli-Responsive Aggregation of High Molar Mass Poly(N,N-Diethylacrylamide)-b-Poly(4-Acryloylmorpholine) in Tetrahydrofuran.

Alexander Plucinski,Mairi Clarke,David Bhella,Marko Pavlovic,Bernhard V K J Schmidt

doi:10.1002/marc.202100656

Abstract

The self-assembly of block copolymers constitutes a timely research area in polymer science with implications for applications like sensing or drug-delivery. Here, the unprecedented aggregation behavior of high molar mass block copolymer poly(N,N-diethylacrylamide)-b-poly(4-acryloylmorpholine) (PDEA-b-PAM) (Mn >400kg mol-1 ) in organic solvent tetrahydrofuran (THF) is investigated. To elucidate the aggregation, dynamic light scattering, cryo-transmission electron microscopy, and turbidimetry are employed. The aggregate formation is assigned to the unprecedented upper critical solution temperature behavior of PAM in THF at elevated concentrations (> 6 wt.%) and high molar masses. Various future directions for this new thermo-responsive block copolymer are envisioned, for example, in the areas of photonics or templating of inorganic structures.

Highlights

An important factor for the structures drug-delivery
PDEA-b-PAM was obtained with a molar mass of Mn = 403 000 g mol−1 and Ð of 1.5 according to SEC-MALS
The synthesis of the high molar mass block copolymer was verified via diffusion-ordered NMR spectroscopy (DOSY) that revealed signals at a diffusion coefficient of 7.5 10−7 cm2 s−1 for both block types (Figure S5, Supporting Information)

Summary

Introduction

An important factor for the structures drug-delivery. Here, the unprecedented aggregation behavior of high molar mass block copolymer poly(N,N-diethylacrylamide)-b-poly(4-acryloylmorpholine) (PDEA-b-PAM) (Mn>400 kg mol−1) in organic solvent tetrahydrofuran (THF) is investigated. Formed in self-assembly and aggregation of polymers, is the molar mass of the block copolymers. In a selective solvent is assigned to the unprecedented upper critical solution temperature behavior of PAM in THF at elevated concentrations (> 6 wt.%) and high molar masses. Overview of the aggregation behavior of poly(N,N-diethylacrylamide)-b-poly(4-acryloylmorpholine) (PDEA-b-PAM) in THF, depending on molar mass or concentration.

Results

Conclusion