This inventor holds 3 USPTO granted patents. Top assignee: Witco Corporation. Active years: 1997-2000.
Company Filing History:
Years Active: 1997-2000
Title: Wally L Chang: Innovator in Water-Dispersible Polyurethanes
Introduction
Wally L Chang is a notable inventor based in Naperville, IL (US). He has made significant contributions to the field of polymer chemistry, particularly in the development of water-dispersible polyurethanes. With a total of 3 patents to his name, Chang's work has had a considerable impact on various applications in the industry.
Latest Patents
Chang's latest patents include innovative processes for producing water-dispersible polyurethanes. One of his patents, titled "Polyurethane synthesis from functional group terminated polymers," discloses a method for creating these polyurethanes by forming an isocyanate-di-substituted prepolymer and reacting it with a chain extender. This prepolymer is formed by reacting a diisocyanate with an ethylenically unsaturated precursor, which is preferably created through condensation polymerization of reactants. The process also involves sulfonating the ethylenic unsaturation of the polymeric precursor using a sulfonating agent such as bisulfite or metabisulfite.
Another significant patent by Chang focuses on "Functional group terminated polymers containing sulfonate group." This patent outlines a process for producing water-dispersible polymers, particularly condensation polymers like polyesters, polyethers, and polyamides. Similar to his previous work, this process involves forming an ethylenically unsaturated polymeric precursor through condensation polymerization and subsequently sulfonating it.
Career Highlights
Wally L Chang is currently associated with Witco Corporation, where he continues to innovate and develop new materials. His expertise in polymer chemistry has positioned him as a key player in the field, contributing to advancements that enhance the functionality and applicability of various polymers.
Collaborations
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Conclusion
Wally L Chang's contributions to the field of polymer chemistry, particularly in the area of water-dispersible polyurethanes, highlight his innovative spirit and dedication to advancing material science. His patents reflect a commitment to developing processes that improve the functionality of polymers in various applications.