Oxygen Polymethacrylic acid

The benzene ring has an inhibitive effect not only as a part of the macromolecule, but also as a group in additives. For instance, the addition of small amounts of n-pro-pylbenzene under exclusion of oxygen inhibits the degradation of polymethacryl acid methyl ester 1,2-benzanthrene inhibits crosslinking in pure polyisoprene. These examples show that intermolecular protection is possible. However, it is problematic to compare the effectiveness of intra- and intermolecular energy transfer [710]. 

Electron spin resonance spectroscopy has been applied in oxygen stability studies on polymethacrylic acid [8, 9]. 

Use is being made of polymers alone in controlling deposits in boilers up to ISOOlb/in. The treatment solubilizes Ca "", Mg" " , Al" " " and maintains silica in solution. It removes scales from boilers. If polymers are to be used, oxygen must be strictly controlled. The effectiveness of a polymer is determined by its molecular weight and concentration. For example, polyacrylic acid (molecular weight = 20 000) addition reduces scale formation of only 52% compared to polymaleic acid (molecular weight = 5000) which reduces scale formation by 97%. Some typical polymers used are polycarboxylic acid, polymethacrylic acid, styrene and maleic add. 

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