scholarly journals The Permeability and Mechanical Properties of Cellulose Acetate Membranes Blended with Polyethylene glycol 600 for Treatment of Municipal Sewage

2012 ◽  
Vol 16 ◽  
pp. 346-351 ◽  
Author(s):  
Haolong Bai ◽  
Yitong Zhou ◽  
Xuan Wang ◽  
Liping Zhang
Keyword(s):  
Mechanical Properties ◽  
Polyethylene Glycol ◽  
Cellulose Acetate ◽  
Municipal Sewage ◽  
Cellulose Acetate Membranes

Effect of Polyethylene Glycol (PEG) on Molten Plasticized Cellulose Acetate (CA)

2013 ◽  
Vol 830 ◽  
pp. 172-175
Author(s):  
Cheng Zhi Chuai ◽  
Zhi Zhang
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Tensile Strength ◽  
Polyethylene Glycol ◽  
Flexural Strength ◽  
Cellulose Acetate ◽  
Flexural Modulus ◽  
Degree Of Polymerization ◽  
Maximum Elongation ◽  
Elongation At Break

Ethylene glycol (EG) and polyethylene glycol (PEG) were added as plasticizers to improve the processing performance of cellulose acetate (CA). The CA with 30% plasticizers were melted by HAAKE at 200 °C. The effects of EG and PEG (degree of polymerization in 200-800) on rheological properties and mechanical properties of CA were investigated. The results show that the plasticizing time, equilibrium torque and melt viscosity of the plasticizing system increase with the increase of PEG molecular weight, while the processing performance decreased. The tensile strength of the system decrease as the PEG molecular weight increased. The plasticizing system which contents 30% PEG-200(degree of polymerization is 200) shows the maximum elongation at break. The minimum values appeared in both flexural strength and flexural modulus in the CA/PEG-200 system.

scholarly journals Additives Incorporated in Cellulose Acetate Membranes to Improve Its Performance as a Barrier in Periodontal Treatment

2021 ◽  
Vol 2 ◽  
Author(s):  
Mariana Fornazier ◽  
Patricia Gontijo de Melo ◽  
Daniel Pasquini ◽  
Harumi Otaguro ◽  
Gabriela Ciribelli Santos Pompêu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cellulose Acetate ◽  
Physiological Solution ◽  
Point Of View ◽  
Lignin Concentration ◽  
Physical Chemical ◽  
Long Run ◽  
Cellulose Acetate Membranes ◽  
Sample Weight Loss ◽  
Calcium Glycerophosphate

In this study, we prepared cellulose acetate membranes, by means of casting mold, incorporated with two additives, sodium carboxymethyl lignin and calcium glycerophosphate, in order to improve properties for periodontal applications. The membranes were characterized from the morphological, structural, thermal and mechanical point of view, as well as by physiological pH tests. The results showed that membranes with additives improve the physical-chemical and mechanical properties, especially when the two additives are present in the same membrane, which can be attributed to the important synergy between them. The most significant effects occur in increasing the thickness and decreasing the density, which reflects in the porosity of the membranes, although the added amounts do not exceed 1.4%. A 1% increase in lignin concentration does not change the thickness and density of the membrane, but that amount of lignin plus 0.4% calcium glycerophosphate increases the thickness of the membrane by 42% and decreases the density by about 6%. Although there is a decrease in mechanical properties, as observed in Young's modulus and crystallinity, the significant and intermittent increase in sample weight loss with both additives in physiological solution indicates that, in the long run, it can be used as a degradable barrier.

Development, Evaluation and Optimization of Osmotic Controlled Tablets of Aceclofenac for Rheumatoid Arthritis Management

2019 ◽  
Vol 9 (1) ◽  
pp. 29-36
Author(s):  
Bijaya Ghosh ◽  
Niraj Mishra ◽  
Preeta Bose ◽  
Moumita D. Kirtania
Keyword(s):  
Rheumatoid Arthritis ◽  
Polyethylene Glycol ◽  
Sodium Chloride ◽  
Cellulose Acetate ◽  
Hydroxypropyl Methylcellulose ◽  
Release Profile ◽  
Polyethylene Glycol 400 ◽  
Permeable Membrane ◽  
Cumulative Release ◽  
The Core

Objective: Rheumatoid arthritis is a dreaded disease, characterized by pain, inflammation and stiffness of joints, leading to severe immobility problems. The disease shows circadian variation and usually gets aggravated in early morning hours. Aceclofenac, a BCS Class II compound is routinely used in the treatment of pain and inflammation associated with rheumatoid arthritis. The objective of this study was to develop an osmotic delivery system of Aceclofenac that after administration at bedtime would deliver the drug in the morning hours. </P><P> Methods: A series of osmotically controlled systems of aceclofenac was developed by using lactose, sodium chloride and hydroxypropyl methylcellulose K100M as osmogens. Cellulose acetate (2% w/v in acetone) with varying concentrations of polyethylene glycol-400 was used as the coating polymer to create semi permeable membrane and dissolution was carried out in 290 mOsm phosphate buffer. Formulation optimization was done from four considerations: cumulative release at the end of 6 hours (lag time), cumulative release at the end of 7 hours (burst time), steady state release rate and completeness of drug release. </P><P> Results: A formulation having swelling polymer hydroxypropyl methylcellulose in the core and lactose and sodium chloride as osmogens, polyethylene glycol-400 (16.39 %) as pore former, with a coating weight of 5% was a close fit to the target release profile and was chosen as the optimum formulation. Conclusion: Aceclofenac tablets containing lactose, HPMC and sodium chloride in the core, given a coating of cellulose acetate and PEG-400 (5% wt gain), generated a release profile for optimum management of rheumatoid arthritic pain.

Effect of the structure of cellulose acetate membranes on their permeability, electrical conductivity and rejection

1990 ◽  
Vol 55 (12) ◽  
pp. 2933-2939 ◽  
Author(s):  
Hans-Hartmut Schwarz ◽  
Vlastimil Kůdela ◽  
Klaus Richau
Keyword(s):  
Electrical Conductivity ◽  
Electrical Properties ◽  
Cellulose Acetate ◽  
Reverse Osmosis ◽  
Water Flux ◽  
Cellulose Acetate Membrane ◽  
Structure Parameters ◽  
Dc Electrical Conductivity ◽  
Cellulose Acetate Membranes

Ultrafiltration cellulose acetate membrane can be transformed by annealing into reverse osmosis membranes (RO type). Annealing brings about changes in structural properties of the membranes, accompanied by changes in their permeability behaviour and electrical properties. Correlations between structure parameters and electrochemical properties are shown for the temperature range 20-90 °C. Relations have been derived which explain the role played by the dc electrical conductivity in the characterization of rejection ability of the membranes in the reverse osmosis, i.e. rRO = (1 + exp (A-B))-1, where exp A and exp B are statistically significant correlation functions of electrical conductivity and salt permeation, or of electrical conductivity and water flux through the membrane, respectively.

Transport properties of Toray's asymmetric cellulose acetate membranes

Desalination ◽  
1985 ◽  
Vol 56 ◽  
pp. 251-260 ◽  
Author(s):  
M. Kurihara ◽  
W. Pusch ◽  
T. Tanaka
Keyword(s):  
Transport Properties ◽  
Cellulose Acetate ◽  
Cellulose Acetate Membranes

Quantitative alkaline phosphatase isoenzyme determination by electrophoresis on cellulose acetate membranes.

1977 ◽  
Vol 23 (1) ◽  
pp. 28-34 ◽  
Author(s):  
W H Siede ◽  
U B Seiffert
Keyword(s):  
Alkaline Phosphatase ◽  
Cellulose Acetate ◽  
Clinical Laboratory ◽  
Kinetic Assay ◽  
Specific Staining ◽  
Cellulose Acetate Membranes ◽  
Alkaline Phosphatase Isoenzymes ◽  
Elution Method ◽  
Routine Clinical Laboratory ◽  
Alkaline Phosphatase Isoenzyme

Abstract We present a new method for quantitative determination of alkaline phosphatase isoenzymes. This method consists of electrophoretic separation on cellulose acetate membranes, special fixation technique to avoid elution and diffusion of enzyme protein during incubation, specific staining, and quantitative evaluation by densitometric measurement. We highly recommend the precedure for routine clinical laboratory use. In all normal individuals we observe two isoenzymes of hepatic origin and one isoenzyme each of osseous, intestinal, and biliary origin. Quantitative normal values are presented. Precision of the method is calculated, the CV being less than 10%. The exactness of densitometric quantification is proved by comparison with kinetic assay of alkaline phosphatase isoenzymes by use of an elution method. Clinical implications of alkaline phosphatase isoenzymograms are reported and discussed in detail.

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