Biomaterial Database

Evaluation of sunlight stability of polyurethane elastomers for maxillofacial use. II. 1979

C C Chu, and T E Fischer

The effect of selected UV stabilizers on the stability of mechanical properties of a polyurethane material, Calthane ND2300, was evaluated. The addition of UV stabilizers prolonged the service life of the systems studied but did not achieve completely satisfactory results. The tensile strength and modulus of elasticity decreased after extended exposure to UV. The rate of decrease, however, was much less for the specimens with UV stabilizers. The polyurethane system that contains a mixture of a UV stabilizer and an antioxidant is considered to be the best of the groups tested, in terms of the percentage of retention of tensile strength and modulus of elasticity. It was also found that elongation at break was increased when the duration of UV aging was increased. This phenomenon occurred in all the systems, with or without UV stabilizers, and can be understood in terms of the concepts of the fragmentation of macromolecules that resulted from UV aging. The physical appearance in conjunction with mechanical property tests are needed to ensure the successful performance of any UV stabilizer.

UI	MeSH Term	Description	Entries
D008447	Maxillofacial Prosthesis	A prosthetic appliance for the replacement of areas of the maxilla, mandible, and face, missing as a result of deformity, disease, injury, or surgery. When the prosthesis replaces portions of the mandible only, it is referred to as MANDIBULAR PROSTHESIS.	Maxillary Prosthesis,Maxillary Prostheses,Maxillofacial Prostheses,Prostheses, Maxillary,Prostheses, Maxillofacial,Prosthesis, Maxillary,Prosthesis, Maxillofacial
D011140	Polyurethanes	A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.	Polyisocyanates,Ostamer,Pellethane,Spandex,Ostamers,Pellethanes,Polyisocyanate,Polyurethane,Spandices
D011474	Prosthesis Design	The plan and delineation of prostheses in general or a specific prosthesis.	Design, Prosthesis,Designs, Prosthesis,Prosthesis Designs
D002627	Chemistry, Physical	The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.	Physical Chemistry,Chemistries, Physical,Physical Chemistries
D004548	Elasticity	Resistance and recovery from distortion of shape.
D013472	Sunlight	Irradiation directly from the sun.	Sunshine
D013499	Surface Properties	Characteristics or attributes of the outer boundaries of objects, including molecules.	Properties, Surface,Property, Surface,Surface Property
D013718	Tensile Strength	The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)	Strength, Tensile,Strengths, Tensile,Tensile Strengths
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D014466	Ultraviolet Rays	That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.	Actinic Rays,Black Light, Ultraviolet,UV Light,UV Radiation,Ultra-Violet Rays,Ultraviolet Light,Ultraviolet Radiation,Actinic Ray,Light, UV,Light, Ultraviolet,Radiation, UV,Radiation, Ultraviolet,Ray, Actinic,Ray, Ultra-Violet,Ray, Ultraviolet,Ultra Violet Rays,Ultra-Violet Ray,Ultraviolet Black Light,Ultraviolet Black Lights,Ultraviolet Radiations,Ultraviolet Ray