scholarly journals Precise Synthesis and Thermoresponsive Property of Poly(ethyl glycidyl ether) and Its Block and Statistic Copolymers with Poly(glycidol)

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3873
Author(s):  
Tingyu He ◽  
Yanqiu Wang ◽  
Atsushi Narumi ◽  
Liang Xu ◽  
Shin-ichiro Sato ◽  
...  
Keyword(s):  
Phase Transition ◽  
Glycidyl Ether ◽  
Solution Temperature ◽  
Multiblock Copolymers ◽  
Phase Transition Behavior ◽  
Critical Solution Temperature ◽  
Upper Critical Solution Temperature ◽  
Protective Groups ◽  
Pentablock Copolymers ◽  
Comprehensive Study

In this paper, we describe a comprehensive study of the thermoresponsive properties of statistic copolymers and multiblock copolymers synthesized by poly(glycidol)s (PG) and poly(ethyl glycidyl ether) (PEGE) with different copolymerization methods. These copolymers were first synthesized by ring-opening polymerization (ROP), which was initiated by tert-butylbenzyl alcohol (tBBA) and 1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)phosphoranylidenamino]-2Λ5,4Λ5-catenadi(phosphazene) (t-Bu-P4) as the catalyst, and then the inherent protective groups were removed to obtain the copolymers without any specific chain end groups. The thermoresponsive property of the statistic copolymer PGx-stat-PEGEy was compared with the diblock copolymer PGx-b-PEGEy, and the triblock copolymers were compared with the pentablock copolymers. Among them, PG-stat-PEGE, PG-b-PEGE-b-PG-b-PEGE-b-PG, and PEGE-b-PG-b-PEGE-b-PG-b-PEGE, and even the specific ratio of PEGE-b-PG-b-PEGE, exhibited LCST-type phase transitions in water, which were characterized by cloud point (Tcp). Although the ratio of x to y affected the value of the Tcp of PGx-stat-PEGEy, we found that the disorder of the copolymer has a decisive effect on the phase-transition behavior. The phase-transition behaviors of PG-b-PEGE, part of PEGE-b-PG-b-PEGE, and PG-b-PEGE-b-PG copolymers in water present a two-stage phase transition, that is, firstly LCST-type and then the upper critical solution temperature (UCST)-like phase transition. In addition, we have extended the research on the thermoresponsive properties of EGE homopolymers without specific α-chain ends.

scholarly journals Phase Transition Behavior of HPMC-AA and Preparation of HPMC-PAA Nanogels

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Risheng Yao ◽  
Jiajia Xu ◽  
Xihua Lu ◽  
Shengsong Deng
Keyword(s):  
Phase Transition ◽  
Driving Force ◽  
Hydroxypropyl Methylcellulose ◽  
Solution Temperature ◽  
Temperature Phase ◽  
Phase Transition Behavior ◽  
Critical Solution Temperature ◽  
Transmission Electron ◽  
Temperature Phase Transition ◽  
Redox Initiator

The lower critical solution temperature (LCST) of hydroxypropyl methylcellulose (HPMC) under mixing with acrylic acid (AA) monomer has been studied by turbidity measurements. It has been found that the LCST of the HPMC was drastically reduced from 60°C to 38°C with the increase of the concentration of AA, while the HPMC is kept at 0.5 wt%. The driving force shifting the LCST is attributed to the hydrogen bonding and hydrophobic interaction of the molecules. Then surfactant-free HPMC-PAA nanogels have been synthesized via the polymerization of AA monomer with the collapsed HPMC as a template or core at their LCST, using KPS and TEMED as redox initiator in the presence of BIS as cross-linking agent. HPMC-PAA nanogels have 50~150  nm diameters characterized by transmission electron microscope and dynamic light scattering. The HPMC-PAA nanogels exhibit the temperature phase transition behaviors, and these nanogels' volume phase transition temperature is close to the LCST of HPMC/AA system.

Upper critical solution temperature (UCST) phase transition of halide salts of branched polyethylenimine and methylated branched polyethylenimine in aqueous solutions

2016 ◽  
Vol 52 (3) ◽  
pp. 509-512 ◽  
Author(s):  
Minwoo Noh ◽  
Sunah Kang ◽  
Yeongbong Mok ◽  
So Jung Choi ◽  
Jeongseon Park ◽  
...  
Keyword(s):  
Phase Transition ◽  
Aqueous Solutions ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Upper Critical Solution Temperature ◽  
Branched Polyethylenimine ◽  
Halide Salts

Halide salts of branched polyethylenimine (b-PEI) and methylated b-PEI exhibited UCST phase transition in aqueous solutions.

Selective Hydrogen Bonding Controls Temperature Response of Layer-by-Layer Upper Critical Solution Temperature Micellar Assemblies

Soft Matter ◽  
2021 ◽  
Author(s):  
Aliaksei Aliakseyeu ◽  
Victoria Albright ◽  
Danielle Yarbrough ◽  
Samantha Hernandez ◽  
Qing Zhou ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Methacrylic Acid ◽  
Temperature Response ◽  
Solution Temperature ◽  
Layer By Layer ◽  
Critical Solution Temperature ◽  
Hydrogen Bonding Interactions ◽  
Upper Critical Solution Temperature ◽  
Lbl Films

This work establishes a correlation between the selectivity of hydrogen-bonding interactions and the functionality of micelle-containing layer-by-layer (LbL) assemblies. Specifically, we explore LbL films formed by assembly of poly(methacrylic acid)...

A polyelectrolyte-containing copolymer with a gas-switchable lower critical solution temperature-type phase transition

2019 ◽  
Vol 10 (2) ◽  
pp. 260-266 ◽  
Author(s):  
Jin-Jin Li ◽  
Yin-Ning Zhou ◽  
Zheng-Hong Luo ◽  
Shiping Zhu
Keyword(s):  
Phase Transition ◽  
Cloud Point ◽  
Lower Critical Solution Temperature ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Type Phase

A polyelectrolyte-containing copolymer with a CO2/N2-switchable cloud point, resulting from the gas-induced alternation of hydrophilicity, was prepared.

Sign in / Sign up

Export Citation Format

Share Document