Process of preparing highly substituted hydroxyalkyl ethers of uninhibited granule starches substantially free of salts and glycols,and resulting products
Abstract
Abstract SUBSTANTIALLY SALT-FREE AND GLYCOL-FREE MONOFUNCTIONAL REACTION PRODUCTS OF UNINHIBITED GRANULE STARCHES WITH HIGH LEVELS OF ALKYLENE OXIDES ARE PREPARED BY A WATER SUSPENSION ETHERIFICATION PROCESS USING AN ALKALINE CATLYST IN COMBINATION WITH AN ALKALI METAL SULFATE. THE ALKALI METAL SULFATE IS ESSENTIAL, AND IT IS USED AT A CONCENTRATION OF A LEAST 3 TO 5 PARTS PER 100 PARTS OF WATER. ALTHOUGH THE REACTION IS CARRIED TO A HIGH SUBSTITUTION LEVEL MEASURED AS HYDROXYALKYL (D.S.), THE STARCH, ALTHOUGH NOT CROSSLINKED, REMAINS IN NATIVE GRANULE FORM AND IS BOTH FILTERABLE AND WASHABLE. THIS PERMITS SUBSTANTIALLY COMPLETE REMOVAL OF THE SALTS AND SIDE REACTION PRODUCTS BY ORDINARY FILTRATION AND WASHING TECHNIQUES. THE METHOD CAN BE EMPLOYED TO PRODUCE NOVEL STARCH PRODUCTS, WHICH ARE BELIEVED TO CONTAIN MONOFUNCTIONALLY-LINKED OXYALKYL POLYMER CHAINS, AND THE PRODUCTS ARE FREE OF BIFUNCTIONAL CROSS-LINKS.
Inventors
- 👤 Erling T Hjermstad
Bibliographic Details
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