Next Article in Journal
Phospholipid-Coated Mesoporous Silica Nanoparticles Acting as Lubricating Drug Nanocarriers
Previous Article in Journal
Evaluation of the Stability of Polymeric Materials Exposed to Palm Biodiesel and Biodiesel–Organic Acid Blends
Previous Article in Special Issue
Recent Advances in RAFT Polymerization: Novel Initiation Mechanisms and Optoelectronic Applications
Article Menu
Issue 5 (May) cover image

Export Article

Open AccessArticle
Polymers 2018, 10(5), 512; https://doi.org/10.3390/polym10050512

Study of theThermo-/pH-Sensitivity of Stereo-Controlled Poly(N-isopropylacrylamide-co-IAM) Copolymers via RAFT Polymerization

Institute of Organic and Polymeric Materials and Research and Development Center for Smart Textile Technology, National Taipei University of Technology, Taipei 106, Taiwan
*
Author to whom correspondence should be addressed.
Received: 13 April 2018 / Revised: 5 May 2018 / Accepted: 6 May 2018 / Published: 9 May 2018
(This article belongs to the Special Issue RAFT Living Radical Polymerization and Self-Assembly)
View Full-Text   |   Download PDF [5859 KB, uploaded 9 May 2018]   |  

Abstract

In this work, a smart copolymer, Poly(nipam-co-IAM) was synthesized by copolymerization of N-isopropylacrylamide (nipam) and itaconamic acid (IAM) through reversible addition-fragmentation chain-transfer (RAFT) polymerization. Poly(nipam-co-IAM) has been studied previously synthesized via radical polymerization without stereo-control, and this work used cumyl dithiobenzoate and Ytterbium(III) trifluoromethanesulfonate as RAFT and stereo-control agents, respectively. The stereo-control result in this work shows that tacticity affects the lower critical solution temperature (LCST) and/or the profile of phase separation of Poly(nipam-co-IAM). In the pH 7 and pH 10 buffer solutions, the P(nipam-co-IAM) copolymer solutions showed soluble–insoluble–soluble transitions, i.e., both LCST and upper critical solution temperature (UCST) transitions, which had not been found previously, and the insoluble to soluble transition (redissolved behavior) occurred at a relatively low temperature. The insoluble to soluble transition of P(nipam-co-IAM) in alkaline solution occurred at a temperature of less than 45 °C. However, the redissolved behavior of P(nipam-co-IAM) was found only in the pH 7 and pH 10 buffer solutions and this redissolved behavior was more prominent for the atactic copolymers than in the isotactic-rich ones. In addition, the LCST results under our experimental range of meso content did not show a significant difference between the isotactic-rich and the atactic P(nipam-co-IAM). Further study on the soluble-insoluble-soluble (S-I-S) transition and the application thereof for P(nipam-co-IAM) copolymers will be conducted. View Full-Text
Keywords: smart polymer; thermo- and pH-Sensitivity; N-isopropylacrylamide; itaconamic acid; UCST; LCST; soluble-insoluble-soluble transition; re-dissolved behavior smart polymer; thermo- and pH-Sensitivity; N-isopropylacrylamide; itaconamic acid; UCST; LCST; soluble-insoluble-soluble transition; re-dissolved behavior
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Rwei, S.-P.; Chiang, W.-Y.; Way, T.-F.; Tuan, H.N.A.; Chang, Y.-C. Study of theThermo-/pH-Sensitivity of Stereo-Controlled Poly(N-isopropylacrylamide-co-IAM) Copolymers via RAFT Polymerization. Polymers 2018, 10, 512.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top