Effect of N-isopropylacrylamide thermoresponsive blocks on the rheological properties of water-soluble thermoassociative copolymers synthesized via RAFT polymerization

Díaz-Silvestre, Sergio; Thomas, Claude St; Maldonado‐Textle, Hortensia; Rivera-Vallejo, Claudia; León-Gómez, Ramón E. Díaz de; Jiménez‐Regalado, Enrique J.

doi:10.1007/s00396-018-4391-y

Cited by 7 publications

(5 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This could lead to the development of intermolecular interactions which induced an increase the viscosity of the aqueous polymer solution. 57,58 Moreover, results from 1 H NMR measurements of copolymer (A 50 N 50 ) were performed at different temperature from 25 to 60 C showed similar spectra for all analyses (See Figure S2). This finding differs to rheological measurements and can be attributed to the probable formation of alternating structure PAM-alt-PNIPAM where the location of highly soluble PAM moieties impede the phase transition of the thermo-responsive PNIPAM fragments.…”

Section: Steady-state Properties Without Saltmentioning

confidence: 63%

“…It is well known that the lower concentration solution temperature (LCST) of PNIPAM is close to 32°C and could enable a phase separation of macromolecule chains above LCST values conducting to the formation of hydrophobic fragments. This could lead to the development of intermolecular interactions which induced an increase the viscosity of the aqueous polymer solution 57,58 . Moreover, results from 1 H NMR measurements of copolymer (A 50 N 50 ) were performed at different temperature from 25 to 60°C showed similar spectra for all analyses (See Figure S2).…”

Section: Resultsmentioning

confidence: 80%

See 1 more Smart Citation

Synthesis and rheological properties of water soluble ionic copolymers as modifier fluids at high temperature and saline media

Jiménez‐Regalado¹,

Gómez²,

Cadenas‐Pliego³

et al. 2023

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

Polymer flooding depicts an interesting strategy to improve the enhanced oil recovery (EOR). This work aims with the synthesis of ionic thermo‐responsive copolymers able to be used as rheological modifiers for EOR under harsh conditions (250,000 ppm of NaCl at 150°C). Copolymers composed of different molar ratio of acrylamide, N‐isopropylacrylamide and 2‐acrylamide‐2‐methyl‐1‐propanesulfonic acid were prepared in aqueous media via free radical polymerization at 50°C using 4,4′‐azobis(‐4″‐cyanopentanoic) acid (ACPA) as initiator. Nuclear magnetic resonance analyses demonstrated the structure and molar composition of synthesized copolymers. Rheological measurements performed at different concentration from 1 to 8 wt% demonstrated an increase in the viscosity from 2000 to 600,000 mPa.s. Aqueous mixtures of polymer at 5 wt% and NaCl at different concentration (5, 10, 15, 20, and 25 wt%) was analyzed. Copolymer ([PAM]/[PNIPAM] = 50/50) displayed a phase separation at 15 wt% of NaCl. Solutions of polymer at 5 and 25 wt% of NaCl were heated at 150°C for 72 h. Results revealed both thermal stability and saline tolerance of copolymers [PAM]/[PNIPAM]/[PAMPS‐Na] = 25/25/50, 35/35/30, and 50/0/50 under harsh conditions with the absence of phase separation of the brine polymer solutions.

show abstract

Section: Steady-state Properties Without Saltmentioning

confidence: 63%

Section: Resultsmentioning

confidence: 80%

Synthesis and rheological properties of water soluble ionic copolymers as modifier fluids at high temperature and saline media

Jiménez‐Regalado¹,

Gómez²,

Cadenas‐Pliego³

et al. 2023

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

show abstract

“…Thermoresponsive water-soluble polymers have been extensively studied in the last decade, as the temperature is one of the easiest and the most effective stimuli [7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

A temperature, pH, and ion sensitive block copolymer with an unusual phase transition: Monomethoxy polyethylene glycol - block-polyethyleneimine

HAMALOĞLU,

Kosaoğlu,

Tuncel

et al. 2024

Preprint

View full text Add to dashboard Cite

A temperature, pH and ion sensitive, block copolymer, monomethoxypolyethylene glycol (MPEG)–block-polyethyleneimine (PEI) was synthesized by carbodimide activation. MPEG-PEI block copolymer exhibited a thermally reversible phase transition from insoluble to soluble form with increasing temperature at neutral pH. MPEG-PEI chains are insoluble in the temperature range of 4-20oC in an aqueous medium containing 3.5 mM phosphate ion. By increasing temperature, homogeneous and transparent solutions including dissolved copolymer are obtained at temperatures higher than 20oC. The observed thermoresponsive behavior was opposite to that seen with poly(N-isopropylacrylamide). Depending on the phosphate ion concentration, the phase transition temperature for passing from insoluble to soluble form could be also precisely controlled between 4-40oC. The reversible phase transition behavior of MPEG-PEI copolymer was confirmed by ten consecutive heating-cooling cycles between 4 - 50oC. MPEG-PEI copolymer also exhibited another responsivity against pH. More appreciable increase in the average hydrodynamic size with the rising temperature was observed at pH 9.0 with respect to those obtained at pH 5 and 7. Temperature, pH and ion sensitive behavior of MPEG-PEI is documented for the first time. The reversible phase transition of MPEG-PEI is a promising tool which may open novel pathways, particularly for enzyme immobilization and drug release studies.

show abstract

“…[35][36][37][38] Additionally, the aforementioned technique has been widely employed in the polymerization acrylamido monomers leading to the synthesis of different type of materials such as: hydrogels, [39,40] thermo-responsiveness, [41,42] associative polymers, [43,44] and multiblock copolymers. [45][46][47] Recently, Díaz-Silvestre et al [48] reported the synthesis of thermo-associative water soluble multiblock copolymers polyacrylamide (PAM) and PNIPAM through RAFT polymerization using 4,4 0 -azobis-4-cyanopentanoic acid as thermal initiator. In all cases, the resulting (co)polymers contained a molar concentration of PNIPAM inferior to 25%.…”

Section: Introductionmentioning

confidence: 99%

“…Recently, Díaz‐Silvestre et al [ 48 ] reported the synthesis of thermo‐associative water soluble multiblock copolymers polyacrylamide (PAM) and PNIPAM through RAFT polymerization using 4,4′‐azobis‐4‐cyanopentanoic acid as thermal initiator. In all cases, the resulting (co)polymers contained a molar concentration of PNIPAM inferior to 25%.…”

Section: Introductionmentioning

confidence: 99%

Thickening behavior of thermo‐associative water soluble multiblock copolymers under redox RAFT polymerization

Maldonado‐Textle

Jiménez‐Regalado

Thomas

2022

Polymer Engineering & Sci

Self Cite

View full text Add to dashboard Cite

In this study, the synthesis of thermo‐associative water soluble multiblock copolymers is reported. A trithiocarbonate functionalized polyacrylamide (PAM) was prepared and subsequently utilized in the preparation of three series of thermo‐associative copolymers by addition of N‐isopropylacrylamide (NIPAM) and acrylamide (AM) until reaching a nonablock copolymer with four thermo‐associative blocks distributed into the backbone of polymer. Reactions were performed at 25 °C using a tertbutyl hydroperoxyde (TBHP) and ascorbic acid (As.Ac.) as redox initiator, and S,S′‐Bis (α,α’‐dimethyl‐α”‐acetic acid)‐trithiocarbonate (DMAT) as chain transfer agent. The targeted molecular weight (MnTheo) of PAM was maintained constant (10,000 g/mol) while the expected Mntheo of polyN‐isopropylacrylamide (PNIPAM) was varied from 10,000, 15,000, and 20,000 g/mol, respectively. The synthesized copolymers were characterized by infrared (IR), nuclear magnetic resonance (NMR), size exclusion chromatography (SEC) for determining the structure of materials, whereas ultraviolet (UV) analysis allowed to get access to the cloud point temperature (Tcp) of polymers. Rheological analyses were carried out for examining the effect of thermo‐responsive block on the thickening behavior of aqueous polymer solutions. These analyses were performed at different concentration from 1 to 20 wt. % varying the temperature of measurements from 25, 30, 40, 50, 60, and 70 °C. Results confirmed the influence of the size of thermo‐responsive blocks on the viscosity of these copolymers.

show abstract

Effect of N-isopropylacrylamide thermoresponsive blocks on the rheological properties of water-soluble thermoassociative copolymers synthesized via RAFT polymerization

Cited by 7 publications

References 60 publications

Synthesis and rheological properties of water soluble ionic copolymers as modifier fluids at high temperature and saline media

Synthesis and rheological properties of water soluble ionic copolymers as modifier fluids at high temperature and saline media

A temperature, pH, and ion sensitive block copolymer with an unusual phase transition: Monomethoxy polyethylene glycol - block-polyethyleneimine

Thickening behavior of thermo‐associative water soluble multiblock copolymers under redox RAFT polymerization

Contact Info

Product

Resources

About