Intrinsic Viscosities and Osmotic Molecular Weights of Cellulose Acetate Fractions
نویسنده
چکیده
The intrinsic viscosities and osmotically estimated number-average molecular weights of a series of cellulose acetate fractions have been measured. It was found that within t he range of chain lengths investigated (number-average molecular weight, lvin, up to 130,000) the number-average molecular weights are proportional to the intrinsic viscosities in acetone solu t ions, in agreement with Staudinger's rule and the results of Kraemer. An estimate is provided of the r elative homogeneity with respect to molecular size of the fraction s and the starting material from which they were prepared. CONTENTS Page
منابع مشابه
Thermal analysis of cellulose esters prepared from different molecular weight fractions of high α-cellulose pulp
High α-cellulose has been dissolved in two non-degrading solvent systems like dimethyl sulfoxide/paraformaldehyde (DMSO/PF) and N,N-dimethyl acetamide/lithium chloride (DMAc/LiCl) and then fractionated to different molecular weight fractions by regeneration technique. Esters of the different molecular weight fractions of cellulose have been prepared having substitution chain length of C2-C5 usi...
متن کاملThe Ultrafiltration Performance of Cellulose Acetate Asymmetric Membranes: A New Perspective on the Correlation with the Infrared Spectra
Integral asymmetric cellulose acetate (CA) membranes were casted by phase-inversion with formamide varying content - 22, 30 and 34% - as pore promoter. These membranes, CA-22, CA-30 and CA-34, were analyzed by infrared spectroscopy in attenuated total reflection mode (ATR-FTIR) to investigate the porous membrane matrix influence on the polymer/water/solute interactions and the selective ultrafi...
متن کاملDesign and Evaluation of Delayed-Release Osmotic Capsule of Acetaminophen
Hard gelatin capsule filled with acetaminophen, osmotic agent (sorbitol), a release promoter (sodium dodecyl sulfate), coated with a semipermeable cellulose acetate membrane containing a hydrophobic plasticizer (castor oil) and sealed with white bees wax plug was designed. When placed in the sink water penetrates the membrane, dissolves the osmotic agent and increases the osmotic pressure...
متن کاملOsmotic Pressure Study of Protein Fractions in Normal and in Nephrotic Subjects
In serum of patients with nephrosis both albumin and globulin showed by osmotic pressure nearly double the molecular weights of normal albumin and globulin. In the urines of such patients, on the other hand, both proteins showed molecular weights lower even than in normal serum. The colloidal osmotic pressures were measured by the author's method at such dilutions that the van't Hoff law relati...
متن کاملEvaluation of effect of edible coating base on carboxy methyl cellulose, Pectin and osmotic dehydration on drying of Pumpkin
The pumpkin is an important kitchen garden crop with very high nutritional value and long lifetime for storage and lot of fiber that acts as one of the best preventive factors from morbid obesity, hypertension, and cardiac diseases. As pretreatment for dehydration, osmotic dehydration creates maximum possible quality in the product by transfer of water outside the tissue of the nutrient. In thi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2011