Shear and extensional rheology of solutions of modified hydroxyethyl celluloses and sodium dodecyl sulfate

Patruyo, L. G.; Müller, Alejandro J.; Sáez, A. Eduardo

doi:10.1016/s0032-3861(02)00598-0

Cited by 73 publications

(58 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It has been observed many times that hydrophobically modied polymers can form networks based on hydrophobic contact points resulting in increased viscosities compared to their unmodied analogues. 71,87 Adding surfactants to such networks leads to a very pronounced increase in viscosity, oen by several orders of magnitude, 69,71,78,87,89 by rendering the contact points more long-lived and/or frequent. A similar behaviour can be observed for the addition of oppositely charged surfactants to polyelectrolytes and several such experiments have been carried out with cellulose based polyelectrolytes.…”

Section: 727883-88mentioning

confidence: 99%

Complexes of oppositely charged polyelectrolytes and surfactants – recent developments in the field of biologically derived polyelectrolytes

2013

View full text Add to dashboard Cite

We review the work done on complexes between biopolyelectrolytes such as ionically modified cellulose or chitosan and oppositely charged surfactants. Around equimolarity of the charges one typically observes precipitation but for other mixing ratios one may form long-time stable complexes, where structure and rheology depend on the mixing ratio, total concentration and the molecular constitution of the components. In addition, it may be the case that the structures are formed under non-equilibrium situations and therefore depend on the preparation path. The binding is shown to occur cooperatively and the micelles present often retain their shape irrespective of the complexation. However, the rather stiff biopolyelectrolytes may lead to an interconnection between different aggregates thereby forming a network with the corresponding rheological properties. In general, the structure and the properties of the aggregates are rather versatile and correspondingly one can create a wide range of different surfactant-biopolyelectrolyte systems by appropriately choosing the composition. This is very interesting as it allows for formulations with a large range of tuneable properties with ecologically friendly polyelectrolytes for many relevant applications.

show abstract

Section: 727883-88mentioning

confidence: 99%

Complexes of oppositely charged polyelectrolytes and surfactants – recent developments in the field of biologically derived polyelectrolytes

2013

View full text Add to dashboard Cite

show abstract

“…Hydrophobically modified hydroxyethyl cellulose (hmHEC) has been studied extensively over last few decades after its first academic investigation published by Landoll 1982(Maestro et al 2002bChassenieux et al 2010;Zhang 2001;Laschet et al 2004;Zhao and Chen 2007;Gonzalez et al 2005;Patruyo et al 2002). This polymer is synthesized by grafting hydrophobic 'sticker' groups across the hydrophilic backbone of HEC.…”

Section: Introductionmentioning

confidence: 99%

Aqueous solutions of HEC and hmHEC: effects of molecular mass versus hydrophobic associations on hydrodynamic and thermodynamic parameters

Vadodaria

English

2016

Cellulose

View full text Add to dashboard Cite

Aqueous solutions of amphiphilic polymers usually comprise of inter-and intramolecular associations of hydrophobic groups often leading to a formation of a rheologically significant reversible network at low concentrations that can be identified using techniques such as static light scattering and rheometry. However, in most studies published till date comparing water soluble polymers with their respective amphiphilic derivatives, it has been very difficult to distinguish between the effects of molecular mass versus hydrophobic associations on hydrodynamic (intrinsic viscosity [g]) and thermodynamic parameters (second virial coefficient A 2 ), owing to the differences between their degrees of polymerization. This study focuses on the dilute and semi-dilute solutions of hydroxyethyl cellulose (HEC) and its amphiphilic derivatives (hmHEC) of the same molecular mass, along with other samples having a different molecular mass using capillary viscometry, rheometry and static light scattering. The weight average molecular masses (M W ) and their distributions for the nonassociative HEC were determined using size exclusion chromatography. Various empirical approaches developed by past authors to determine [g] from dilute solution viscometry data have been discussed. hmHEC with a sufficiently high degree of hydrophobic modification was found to be forming a rheologically significant network in dilute solutions at very low concentrations as opposed to the hmHEC with a much lower degree of hydrophobic modification which also enveloped the hydrophobic groups inside the supramolecular cluster as shown by their [g] and A 2 . The ratio A 2 M W /[g], which takes into account hydrodynamic as well as thermodynamic parameters, was observed to be less for associative polymers compared to that of the non-associative polymers.

show abstract

“…The solutions of P-12 and P-23 exhibit a Newtonian plateau at low shear rates, followed by an abrupt shear thickening region before the onset of shear thinning. The shear thickening region is characteristic for associative flexible polymers and appears as a result of intermolecular hydrophobic associations [80][81][82]. Although these associations are favorable at a certain degree of coil deformation, they are disrupted at higher shear rates.…”

Section: Microstructure Of the Network Chainsmentioning

confidence: 99%

Self-Healing Hydrogels Formed via Hydrophobic Interactions

Okay

2015

Supramolecular Polymer Networks and Gels

View full text Add to dashboard Cite

Shear and extensional rheology of solutions of modified hydroxyethyl celluloses and sodium dodecyl sulfate

Cited by 73 publications

References 20 publications

Complexes of oppositely charged polyelectrolytes and surfactants – recent developments in the field of biologically derived polyelectrolytes

Complexes of oppositely charged polyelectrolytes and surfactants – recent developments in the field of biologically derived polyelectrolytes

Aqueous solutions of HEC and hmHEC: effects of molecular mass versus hydrophobic associations on hydrodynamic and thermodynamic parameters

Self-Healing Hydrogels Formed via Hydrophobic Interactions

Contact Info

Product

Resources

About