Synthesis of high molecular weight polyacrylamide
Synthesis of high molecular weight polyacrylamide flocculant by radiation polymerization Among various solvents, mixtures of water–tert‐butyl alcohol and water–acetone were found to be suitable for the synthesis of the high molecular weight polyacrylamide.
The increase of temperature from 40 to 80 °C decreases the intrinsic viscosity [η] of the hybrid polymer from 655.3 to 512.2 mL g −1, which means the polymerization reaction conducted at lower temperature of 40 °C is suitable for the production of high-molecular-weight soluble hybrid polymers. A further increase in temperature may accelerate the decomposition and consumption of the initiators markedly, resulting in lack of sufficient initiators to sustain the corresponding
Synthesis of Super-High Molecular Weight Polyacrylamides
The super-high molecular weight polyacrylamide flocculants were synthesized using potassium persulfate/sodium hydrogen sulfite as initiators via free radical solution polymerization. The effects of monomer concentration and initiator dosage on the molecular weight, insoluble fraction and dissolution rate of PAM were investigated.
Cationic polyacrylamide is a derivative of polyacrylamide, a cationic polymer flocculant which has an excellent effect on sewage treatment. Our existing cationic polyacrylamide are mostly prepared by the Mannich reaction ,which has the shortcomings of more unreacted material, low cationic degree, poor stability, short validity, etc. Therefore, a cationic polyacrylamide has been prepared by
SYNTHESIS AND CHARACTERIZATION OF POLYACRYLAMIDE
Low temperatures promote synthesis of high mol ecular weight PAM (Lin, 2001). Actually, elevating the reaction temperature causes decrease in molecular weight on account of increase in the rate of
Synthesis of very low molecular weight polyacrylamide Under nitrogen atmosphere, a mixture of acrylamide monomer (10gm), thioglycolic acid (0.20gm) and tetrahydrofuran (THF) (20ml) were placed in 500 ml five-necked Pyrex glass reactor equipped with a reflux
US4617359A - High molecular weight polyacrylamide
This invention discloses a process for the polymerization of acrylamide and for the copolymerization of acrylamide with other monomers. It employs a ferrous/hydroperoxide redox initiator system that greatly enhances the molecular weight of the polymer formed. These high molecular weight acrylamide polymers offer outstanding advantages in enhanced oil recovery as injection water viscosifiers.
Polymeric flocculants because of less needed dose are economically used. Polymeric flocculants divided to three categories: nonionic, anionic and cationic those are almost from polyacrylamide group. Studying mechanisms of flocculation, one of the main factors that enhance flocculation is molecular weight of polymer.
Synthesis, characterization and flocculation activity
The purpose of this paper is to synthesize a new hybrid flocculant Fe(OH) 3 –polyacrylamide (abbr. as FHPAM) and assess its flocculation effect on kaolin suspensions. The study was conducted to investigate the factors which affect molecular weight and flocculation activities of FHPAM and determine its optimal operating conditions.
The increase in. the molecular weight of the starting polymer was found to be 21%. vxx These results indicate the efficiency and convenience of using ACP-Ce(IV) combined system to prepare high molecular weight PAA in aqueous solution via a two-step procedure which avoids the problems associated with aqueous gel.
Synthesis and Flocculation Characteristics of Konjac
The results show that the optimal experimental condition is the hydroxamic acid flocculants contains 10.5% p-ethylphenylethylene and the molecular weight of synthesized product is 11x10(6); The
High molecular weight copolymers were achieved by applying powder-like synthesis process with intrinsic viscosity of final products as high as 12.98 dl/g for anionic flocculant and 10.74 dl/g for
- Is starch a biodegradable polymer?
- Starch is a natural polysaccharide, renewable, relatively cheap, abundant, and biodegradable polymer produced by plants as a reservoir of stored energy [ 22 ]. Starch is a blend of amylose and amylopectin, both consisting of α- d -glucose rings linked together via a α- d - (1,4) and/or α- d - (1,6) bonds.
- Is native starch a hydrophilic polymer?
- It is a hydrophilic polymer containing a multitude of hydroxyl groups with a reactivity comparable to alcohols. Native starch shows a considerably low absorption ability and cannot be used directly as an absorbent. To improve absorption, it is necessary to modify native starch by introducing active groups with chelating and sorption abilities.
- What is a high molecular weight nonionic polyacrylamide?
- High-molecular-weight nonionic polyacrylamides are routinely used in the mineral processing industries as thickeners and flocculants , , . 34.2.5. Polyacrylamide product forms The product types for polyacrylamides are solutions, liquids (emulsion or dispersion), and dry powders.
- Is native starch more stretchable than ungrafted starch?
- It also can be found that the four native starch films exhibit higher tensile strength and lower breaking elongation in comparison with their grafted starch film. The observation implies that films from the grafted starches are more stretchable than ungrafted starches.
