Study of rheological behavior of hydrophobically modified hydroxyethyl cellulose

Li, Qin; Ye, Lin; Cai, Yi; Huang, Ronghua

doi:10.1002/app.23593

Cited by 20 publications

(18 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Now there have appeared large quantities of literatures concerning of this kind of polymers [23][24][25][26][27][28][29]. After partial hydrophobization, the cellulose derivatives can be dissolved in common organic solvents, which makes the further functionalization much easier and better controlled.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of hydrophobic long-chain fatty acylated cellulose and its self-assembled nanoparticles

Guo

Wang

et al. 2012

Polym. Bull.

View full text Add to dashboard Cite

In this paper, a series of cellulose-based hydrophobic associating polymers were prepared by homogeneous acylation of microcrystalline cellulose with long-chain acyl chlorides including octanoyl, lauroyl, and palmitoly chlorides in the solvent of N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) using pyridine as acid scavenger. Through controlling the chain length of fatty acyl chlorides and the molar ratio of acyl chlorides vs anhydroglucose unit, the hydrophobic cellulose derivatives with degrees of substitution in the range of 0.02-1.75 were successfully obtained. The chemical structures and properties of these hydrophobic derivatives were characterized by elemental analysis, FT-IR, CP/MAS 13 C NMR, X-ray diffraction, and the thermogravimetry analysis. It was also found that, the cellulose-based polymers achieved an excellent solubility in organic solvents, such as benzene, methylbenzene, and pyridine, with the introduction of hydrophobic side chain into the cellulose backbone. Furthermore, it was found that these hydrophobic cellulose derivatives could self-assemble into spherical nanoparticles in aqueous solution, which indicates a tremendous potential of applications in pharmaceutical and medical fields.

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of hydrophobic long-chain fatty acylated cellulose and its self-assembled nanoparticles

Guo

Wang

et al. 2012

Polym. Bull.

View full text Add to dashboard Cite

show abstract

“…in 2005 reported hydroxyethyl cellulose in combination with bromododecane increased viscosity and caused thermal stability. [10] Gallardo et al . in 2006 investigated rheological properties of ethylcellulose latex.…”

Section: Resultsmentioning

confidence: 99%

Rheological behavior and stability of ciprofloxacin suspension: Impact of structural vehicles and flocculating agent

Moghimipour¹,

Rezaee²,

Salimi³

et al. 2013

J Adv Pharm Technol Res

View full text Add to dashboard Cite

Ciprofloxacin is a fluoroquinolone and is used against a broad spectrum of gram-negative and gram-positive bacteria. The aim of the study is to investigate the effect of structural vehicles and other formulating factors on physical stability and rheological behavior of ciprofloxacin suspension. To formulate the suspensions, the effect of glycerin and polysorbate 80 as wetting agents was evaluated. Then to achieve controlled flocculation, different concentrations of sodium chloride and calcium chloride were added. After choosing suitable wetting and flocculating agents, structural vehicles such as sodium carboxyl methyl cellulose (NaCMC), hydroxypropylmethylcellulose (HPMC) and Veegum were evaluated. Physical stability parameters such as sedimentation volume, the degree of flocculation and the ease of redispersion of the suspensions and growth of crystals were evaluated. After incorporation of structural vehicles, the rheological properties of formulations containing were also studied to find out their rheological behavior. According to the results, suspension containing glycerin (0.2% w/v) and sodium chloride (0.05% w/v) as wetting agent and flocculating agent, respectively, were the most stable formulations regarding their F and N. Microscopic observations showed the growth of crystals in ciprofloxacin suspension in formulation without excipients and the minimum amount of crystal growth was seen in suspension containing NaCMC (0.25% w/v), Veegum (0.1% w/v) and NaCl (0.05% w/v). Rheological studies showed that almost all of the formulations had psuedoplastic behavior with different degree of thixotropy. The formulation containing NaCMC (0.25% w/v), Veegum (0.1% w/v) and NaCl (0.05% w/v) was the most stable formulation. It may be concluded that by altering the amount ratios of formulation factors, the best rheological behavior and the most proper thixotropy may be achieved.

show abstract

“…The decrease in viscosity of the composite dispersion might have been caused by a reduction of intra-molecular hydrogen bonding of chitosan and a decrease in hydrogen-bonded hydration of chitosan, while heating did not affect the hydration of magnesium aluminum silicate, because magnesium aluminum silicate dispersions were prepared and hydrated using hot water in the preparation process (16). Li et al in 2005 reported that hydroxyethyl cellulose in combination with bromododecane increased viscosity and caused thermal stability (17). …”

Section: Discussionmentioning

confidence: 99%

Influence of Flocculating Agents and Structural Vehicles on the Physical Stability and Rheological Behavior of Nitrofurantoin Suspension

Moghimipour

Salimi

Rezaee³

et al. 2014

Jundishapur J Nat Pharm Prod

View full text Add to dashboard Cite

Background:Nitrofurantoin is a nitrofuran antibiotic that has been used for treatment of urinary tract against positive and negative bacteria. Objectives: The aim of this study was to evaluate the effect of structural vehicles and flocculating agents on physical stability and rheological behavior of nitrofurantoin suspension. Materials and Methods: To formulate the suspensions, the effect of glycerin and polysorbate 80 as wetting agents was evaluated and their particle sizes were determined using the sieve method. Then to achieve controlled flocculation, sodium citrate and aluminum chloride were added. After choosing the suitable wetting and flocculating agents, structural vehicles such as sodium carboxyl methyl cellulose and Veegum were evaluated individually and in combination. In addition, the effect of sorbitol on density of continuous phase and some physical stability parameters such as sedimentation volume, degree of flocculation and ease of redispersion of the suspensions were evaluated. After incorporation of structural vehicles, the rheological properties of formulations were also determined to find their flow behavior. Results: According to the results, glycerin (0.2%) and sodium citrate (0.3%) had the best effect on the suspension stability as wetting and flocculating agents, respectively. Rheological properties of formulations showed pseudoplastic behavior with some degree of thixotropy. Conclusions: In conclusion, the suspension containing Veegum 1%, sodium carboxy methyl cellulose 1%, glycerine 0.2%, sodium citrate 0.3% and sorbitol 20 % was chosen as the most physically stable formulation.

show abstract

Study of rheological behavior of hydrophobically modified hydroxyethyl cellulose

Cited by 20 publications

References 10 publications

Synthesis and characterization of hydrophobic long-chain fatty acylated cellulose and its self-assembled nanoparticles

Synthesis and characterization of hydrophobic long-chain fatty acylated cellulose and its self-assembled nanoparticles

Rheological behavior and stability of ciprofloxacin suspension: Impact of structural vehicles and flocculating agent

Influence of Flocculating Agents and Structural Vehicles on the Physical Stability and Rheological Behavior of Nitrofurantoin Suspension

Contact Info

Product

Resources

About