Nonionic polymer surfactants

Landoll, L. M.

doi:10.1002/pol.1982.170200625

Cited by 8 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This behavior does not indicate a classical overlap but the presence of a rheologically significant network across the system. This phenomenon has been reported in carboxymethyl cellulose (Charpentier-Valenza et al 2005), carboxymethyl pullulans (Simon et al 2003) and hmHEC (Maestro et al 2002a;Landoll 1982). As explained in the theory section, these studies suggest that the aggregates of more than one polymer chain exist even at very low concentrations of amphiphilic polymers.…”

Section: Calculation Of Intrinsic Viscositysupporting

confidence: 71%

“…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%

“…At a concentration below the critical overlap concentration c* (the way it is understood for a non-associative polymer with the same degree of polymerization), the formation of a rheologically significant supramolecular network often results in deviation from the viscometric behavior as predicted by the well known Huggins equation (Landoll 1982). This is a common phenomenon among many associative polymers, such as the hydrophobic derivatives of both carboxymethyl cellulose (Charpentier-Valenza et al 2005) and carboxymethyl pullulans (Simon et al 2003), and the hmHEC (Maestro et al 2002a;Landoll 1982). As an alternative approach, many different empirical methods (i.e.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

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

Section: Calculation Of Intrinsic Viscositysupporting

confidence: 71%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

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

show abstract

“…In the recent years, the cellulose based on material functional has been receiving increasing attention as it does [4][5][6][7][8][9][10][11][12][13][14][15] . The amphiphilic cellulose derivatives, which were synthesized through the reaction of nonionic cellulose ethers like hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC) and methylcellulose (MC) with long-chain n-alkyl epoxides, was first studied at 1982 by Landoll [16] . Science then, a large part of the work about the cellulose derivatives bearing various hydrophobic residues, such as alkyl groups, bulky phenoxyhydroxypropyl groups, poly (e-caprolactone) segments, and poly(methyl methacrylate) segment, have been successfully synthesized [17][18][19][20][21][22][23][24][25] .…”

Section: Introductionmentioning

confidence: 99%

Preparation of cellulose copolymer grafted polylactide(PLA) by the microwave method

Duan

Han

Yang

2012

Proceedings of 2012 International Conference on Biobase Material Science and Engineering

View full text Add to dashboard Cite

We prepare polylactide-cellulose (PLA -cellulose) by microwave irradiation method with lignocellulose as raw material and characterized by infrared spectroscopy (IR) and Xray diffraction. The results show that polylactide can be graft on to the cellulose surface by microwave irradiation method. The grafting rate can be achieved nearly 350% when the proportion of the amount of cellulose and lactide from 10-90wt%. The cellulose-based copolymer has hydrophobic segments and can be used to release hydrophobic drugs.

show abstract

“…The hydrophobes associate with one another in aqueous solutions at low concentrations, and thereby increase the viscosity of the solution at low shear frequencies [21]. Examples of commercial associative thickeners include hydrophobically modified HEC (HMHEC) [22], ethoxylated urethane (HEUR) [23,24], and alkali-soluble emulsion (HASE) [25][26][27]. Enzyme catalysis can be used to put a hydrophobic unit onto a cellulose derivative.…”

Section: Addition Of Hydrophobic Substituentsmentioning

confidence: 99%

Enzyme-Catalyzed Modifications of Polysaccharides and Poly(ethylene glycol)

Cheng

2012

Polymers

View full text Add to dashboard Cite

Polysaccharides are used extensively in various industrial applications, such as food, adhesives, coatings, construction, paper, pharmaceuticals, and personal care. Many polysaccharide structures need to be modified in order to improve their end-use properties; this is mostly done through chemical reactions. In the past 20 years many enzyme-catalyzed modifications have been developed to supplement chemical derivatization methods. Typical reactions include enzymatic oxidation, ester formation, amidation, glycosylation, and molecular weight reduction. These reactions are reviewed in this paper, with emphasis placed on the work done by the authors. The polymers covered in this review include cellulosic derivatives, starch, guar, pectin, and poly(ethylene glycol).

show abstract

Nonionic polymer surfactants

Cited by 8 publications

References 0 publications

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

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

Preparation of cellulose copolymer grafted polylactide(PLA) by the microwave method

Enzyme-Catalyzed Modifications of Polysaccharides and Poly(ethylene glycol)

Contact Info

Product

Resources

About