Polyacrylamide-coacrylates

Minerals. The polymer used in this study is partially hydrolysed polyacrylamide (HPAM), supplied by Allied Colloids Ltd, Low Moor, Bradford, West Yorkshire, England, UK. Approximately 10mol% of the monomer units are hydrolysed and are present as sodium acrylate with a polyacrylamide-coacrylate copolymer having a molecular mass of approximately 6 x lO D. The study minerals quartz, kaolinite and feldspar were collected from the Lee Moor China Clay Pit in Devon, UK. Mica was obtained in sheet form from Agar Scientific. 

The solution viscosity of aqueous polyacrylamide-coacrylates decreases drastically within several weeks (Fig. 17). The behavior is similar to that of PAAm. 

Within this group, the linear polymers have been most intensively studied and researched. The main area of interest lies in water-soluble polymers. However, there have also been many studies into organic solutions, although there exist problems with odor and toxicity in the case of analytical studies. Among the water-soluble additives, tests were made especially on polyethyleneoxide (PEO), polyacrylamide and the coacrylates (PAAm, PAAm/AAcNa), polyacrylic add (PAA), guar gum (GG), carboxymethylcellulose (CMC) and sodium salts, as well as hydroxyethylcellulose (HEC). From these tests, PEO proved to be the most effective flow improver, followed closely by PAAm, which is somewhat more stable than PEO in turbulent flow. 

Na SO ). It can be clearly seen that within the homologous series 40/1, the effectiveness of the low-saponified samples is greater than that of the starting polyacrylamide. A difference between 13% and 30% saponified coacrylates is, however, barely distinguishable. A differentiation in the direction of decreasing effectiveness is possible solely for c = 5 ppm ... 

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