Influence of surfactant properties on thermal behavior and sol–gel transitions in surfactant‐HPMC mixtures

Joshi, Sunil Chandrakant; Chen, Bin

doi:10.1002/app.30317

Cited by 12 publications

(11 citation statements)

References 27 publications

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“…The electrostatic repulsions between ionic heads of the amphiphile molecules tend to change the way the polymer chains align with respect to other. HPMC is found to interact with both anionic and cationic surfactants as compared to the other nonionic polymers, interaction of which generally depends on the conditions of the interacting environment [35][36][37] . HPMC has an amphiphilic behavior and shows a considerable surface activity.…”

Section: Resultsmentioning

confidence: 99%

Modulation of Aggregation Behaviour of Amphiphlic Drug and Surfactant Mixture under the Influence of Neutral Polymer

Azum¹,

Rub²,

Asiri³

et al. 2014

Asian J. Chem.

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The interaction of non-ionic surfactant, Triton X-114 (TX-114) with amphiphilic drug i.e., imipramine hydrochloride (IMP) has been investigated by surface tension measurement in the absence and presence of hydroxypropyl methylcellulose (HPMC) polymer. In the presence of the HPMC the plots of surface tension versus concentration of TX-114 + IMP mixed system show interesting features (i.e., two break points). The two break points attributed to the occurrence of two kind of aggregation process. In the presence of HPMC, the first break is close to that in pure water, can be regarded as critical aggregation concentration (cac), whereas second one is 2-3 times higher than the first one and can be attributed to the polymer bound micelles. The interfacial and bulk behavior was investigated using various theoretical models of Clint, Rosen, Rubingh etc. Synergism was observed in all binary combinations in the micelle and at the interface with or without the HPMC. Various thermodynamic parameters have been calculated with the help of regular solution theory (RST) and pseudo phase model for micellization.

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Section: Resultsmentioning

confidence: 99%

Modulation of Aggregation Behaviour of Amphiphlic Drug and Surfactant Mixture under the Influence of Neutral Polymer

Azum¹,

Rub²,

Asiri³

et al. 2014

Asian J. Chem.

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“…The aggregation number of the small micelles formed on polymeric chains is $30 126 . The formation of ''surfactant-polymer complex'' is energetically more favorable than the formation of ''surfactant micelles'' 125,127 . The addition of more surfactant leads to the formation of micelles in water as critical micellar concentration (CMC) is then attained 127 .…”

Section: Surfactantsmentioning

confidence: 99%

“…The SLS molecules displace the water cages and attach to the methoxyl domains either as monomers or small micelles of low-aggregation number. Such binding occurs through adsorption or cluster formation until saturation 124,125,127 . Swelling of the polymer, and hence agglomerate formation, can thus be avoided.…”

Section: Surfactantsmentioning

confidence: 99%

Co-processing as a tool to improve aqueous dispersibility of cellulose ethers

Sharma

Modi

Bansal

2015

Drug Development and Industrial Pharmacy

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Cellulose ethers are important materials with numerous applications in pharmaceutical industry. They are widely employed as stabilizers and viscosity enhancers for dispersed systems, binders in granulation process and as film formers for tablets. These polymers, however, exhibit challenge during preparation of their aqueous dispersions. Rapid hydration of their surfaces causes formation of a gel that prevents water from reaching the inner core of the particle. Moreover, the surfaces of these particles become sticky, thus leading to agglomeration, eventually reducing their dispersion kinetics. Numerous procedures have been tested to improve dispersibility of cellulose ethers. These include the use of cross-linking agents, alteration in the synthesis process, adjustment of water content of cellulose ether, modification by attaching hydrophobic substituents and co-processing using various excipients. Among these, co-processing has provided the most encouraging results. This review focuses on the molecular mechanisms responsible for the poor dispersibility of cellulose ethers and the role of co-processing technologies in overcoming the challenge. An attempt has been made to highlight various co-processing techniques and specific role of excipients used for co-processing.

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“…Xu et al (Xu et al, 2006) found that as the ionic strength increased, the phase transition temperature of HPMC decreased with a negative linear correlation. Besides, Joshi et al (Joshi & Chen, 2009) investigated how surfactants affected sol-gel transformation temperature in aqueous HPMC/surfactant mixtures and discovered that they can either increase or suppress the LCST of HPMC aqueous solution. The in uence of substituted phenols on HPMC phase transition was examined by Banks et al (Banks et al, 2014), it is observed that phase transition temperature was suppressed concentration dependently.…”

Section: Introductionmentioning

confidence: 99%

Phase Transition Behaviors of Hydroxypropyl Methylcellulose Induced By Small Molecular Weak Acids

Xu¹,

Zhao

2021

Preprint

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In this paper, phase change material hydroxypropyl methylcellulose (HPMC) was chosen to investigate the influence of small molecular weak acids on its phase transition temperature. The results showed that all of the chosen small molecular weak acids such as acrylic acid (AA), methacrylic acid (MAA), DL-lactic acid (LA), citric acid (CA) and acetic acid (AAc) can trigger the decrease of phase transition temperature of HPMC at different pH. With the increase of pH, AA, LA, CA and AAc can further lower the phase transition temperature, on the contrary, the phase transition temperature of HPMC increased with MAA. The change range of LCST was largest around pKa compared with other pH values because triggering effect changed gradually from hydrogen bonding effect to salt effect upon the increase of pH. Besides, phase transition temperature can also be reduced by the increase of acid concentration. This is attributed to smaller distance between molecules caused by higher concentration leading to stronger hydrogen bonding effect or salt effect. This paper provided a new perspective to modulate the LCST of phase change material by small molecular weak acids at different pH.

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Influence of surfactant properties on thermal behavior and sol–gel transitions in surfactant‐HPMC mixtures

Cited by 12 publications

References 27 publications

Modulation of Aggregation Behaviour of Amphiphlic Drug and Surfactant Mixture under the Influence of Neutral Polymer

Modulation of Aggregation Behaviour of Amphiphlic Drug and Surfactant Mixture under the Influence of Neutral Polymer

Co-processing as a tool to improve aqueous dispersibility of cellulose ethers

Phase Transition Behaviors of Hydroxypropyl Methylcellulose Induced By Small Molecular Weak Acids

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