Milliken + Co

Jenci Kurja

Stephane Berghmans

Robert C Kerr

Bhawan Patel

Geoffrey R Haas

David L Morris

Carolina Mateus

This disclosure relates generally to molded rubber articles such as the type used in water contact applications. More particularly, this disclosure is directed to molded rubber articles containing antimicrobial agents that control biofilm growth on the surface of the molded article. The molded rubber article is comprised of curable rubber compounds and a combination of both inorganic silver-containing antimicrobial agents and organic antimicrobial agents. An exemplary molded rubber article comprises ethylene propylene diene monomer rubber, silver-containing ion exchange antimicrobial agent, and an organic antifungal agent such as zinc pyrithione.

Antimicrobial rubber formulations and molded article

Unique transparent plastic (preferably though not necessarily polypropylene) articles that can be tailored to become opaque when exposed to a sufficiently high temperature and which returns to substantially the same transparency level upon cooling are provided. Such formulations include polymeric constituents that exhibit melting temperatures well below that for the majority clarified polypropylene, and thus which appear to become amorphous upon exposure to temperatures above such a lower melting temperature, thereby affecting the crystalline formation of the clarified polypropylene to the extent that opacity dominates the appearance thereof. Such lower melting temperature polymeric constituents include species such as low melt flow (up to 10) metallocene polyethylene and/or low density polyethylene, both of which exhibit melting temperatures of from about 60 to about 100&deg; C., well below the typical polypropylene melting temperatures of roughly about 150&deg; C. for homopolymer and about 165&deg; for typical random copolymer. Preferably, as well, the melt flow for the polypropylene may be anywhere from about 1 to about 20, with the most preferable formulation comprising polyethylene and polypropylene components exhibiting similar melt flow properties (e.g., with a difference of at most 5 units) for better mixing results. Methods of producing such temperature sensitive transparent polypropylene formulations and articles are also encompassed within this invention.

Transparent plastic articles comprising certain polymeric components to provide temporary and reversible opacity characteristics

Unique transparent polypropylene articles that can be tailored to become opaque when exposed to a sufficiently high temperature and which returns to substantially the same transparency level upon cooling. Such formulations include non-polypropylene polymeric constituents that exhibit refractive index measurements similar to the base clarified polypropylene at lower temperatures, as well as melting temperatures well below that for the base clarified polypropylene. Upon exposure to temperatures in close proximity to the melting temperature of the non-polypropylene polymeric constituents, the refractive index for such constituents will then become modified to the extent that the overall article appears at least partially opaque. In particular, the non-polypropylene polymeric constituents should exhibit melting temperatures well below that for the base clarified polypropylene, from about 60 to about 100&deg; C. (well below the typical polypropylene melting temperatures of roughly about 160-190&deg; C. for homopolymer and about 140-170&deg; C. for typical random copolymer, both nucleated or non-nucleated). In this manner, a temperature sensitivity measuring thermoplastic article may be provided, and may be tailored to specific temperature ranges dependent on the melting temperatures exhibited by the non-polypropylene polymeric constituents. Methods of measuring temperature levels via the transformation of transparent polypropylene formulations to at least partially opaque versions thereof are also encompassed within this invention.

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Knokke-Heist, Belgium

Jenci Kurja