Grafting alcohols, acid effect

A theory for this acid effect has been developed essentially from the wool and cellulose work (3,4). Recently, in a brief communication, we reported analogous acid enhancement effects in the radiation grafting of monomers such as styrene in methanol to nonpolar synthetic backbone polymers like polypropylene and polyethylene (5). In the present work, detailed studies of this acid enhancement effect are discussed for the radiation grafting of styrene in various solvents to polyethylene. The results are fundamentally important since most of the experiments reported here have been performed in solvents such as the low molecular weight alcohols which, unlike cellulose and wool systems, do not swell polyethylene. 

TABLE I. Acid Effect in Radiation Grafting to Polyethylene using Styrene in Low Molecular Weight Alcohols.a... 

Acid Effect in Grafting With Isomeric Alcohols. With the isomeric propanols and butanols, some unexpected results were obtained both in the presence and absence of acid (Table II). 

Table XI. Effect of Acid on Gamma Ray Grafting of Styrene Cellulose Acetate at High Dose in Alcohols"...

The preparation of pol)rmeric catalysts and substrates containing imidazole groups and nitro-phenyl esters, respectively, grafted onto crosslinked polystyrene beads has been described and the effects of the acyl chain length in the substrate in the aqueous alcohol solvent systems on the rate of hydrolysis of 3-nitro-4-acyloxybenzoic acid substrates catalyzed by insoluble catalysts were determined. 

Table 1. Effect of Sulfuric Acid (0.02 M) on Radiation Grafting of Styrene in Low Molecular Weight Alcohols to Polypropylene Film ...

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