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Light Stabilizers and UV Absorbers help protect plastics from sun damage

Light Stabilizers and UV Absorbers help protect plastics from sun damage

Polymers used in outdoor applications tend to degrade as they are prone to ultra violet and infra red radiation from the sunlight. Protection from UV radiation is important in polymer products, as UV radiation can stimulate molecules to an extent so as to break their chemical bonds that can release highly reactive radicals, capable of destroying other molecules. This reaction leads to formation of further radicals, hence degradation of the polymer proceeds indefinitely in a chain reaction, which if not interrupted, leads to the plastic component to lose its mechanical, optical and color properties. Excessive exposure to ultraviolet light can cause damage to the plastic, resulting in loss of mechanical properties, change in colour, generation of off tastes and odours, fading of the print, etc. Besides damaging the plastic, UV radiation can adversely affect substances within the plastic such as food and beverages, pharmaceutical products, household, cosmetic and personal care products - by leading to colour fading of food, accelerated oxidation of oils and fats and loss of vitamin content in fruit juice and milk.
Croda Polymer Additives produces a range of ultra-fine metal oxides which deliver superior UV protection and significantly improved transparency compared to traditional metal oxide powders. The unique patented technology of the Solasorb range provides greater dispersion and clarity than ever before. Unlike commonly used organic UV absorbers, the stable dispersions are proven to deliver low migration and long-term UV protection. Primarily aimed at clear film and bottle packaging applications, it protects contents from the harmful effects of UV light, giving consumer products greater shelf appeal. Extensive testing showed that a commercial sports drink experienced severe colour loss after just 24 hours� exposure in a UV cabinet. By using a 65�m shrink sleeve containing 1.3% Solasorb UV-200F, this problem was virtually eliminated, without compromising the appearance of the brand. The range is available as fully dispersed liquids or in polymer carriers under the AtmerTM concentrates range which are suitable for use in both PE and PP. It finds application in
• Beverage packaging
• Food packaging
• Toiletries & cosmetics packaging
BASF�s Uvinul® 5050 H belongs to a group of hindered amine light stabilizers (HALS), and is used for to light stabilization of polyolefins. It is a highly effective light stabilizer for polyolefins, ABS and polyamide, which also exhibits very good compatibility with pigments. The melting range of 155-160°C is ideally suited for extrusion for these polymers. Polyolefins thus stabilized offer extreme long-term stability and are excellent to process. Uvinul® 5050 H offers a range of advantages:
• It has significantly little effect on alkali-sensitive pigments and minimal interaction with acids. The latter plays an important role especially in agricultural films. This property also makes it a suitable stabilizer for PVC.
• In tape production, it is outstanding in respect of its extremely low water carry-over. Its use as an additive minimally alters the surface, such that affinity to water is not significantly increased.
• Its use to stabilize polyolefin films permits lower welding temperatures than with other oligomeric HALS compounds. This makes polyolefin films easier and quicker to weld. Especially in packaging lines, in which stretch or shrink film covers are welded, you are not only able to save time but also the associated costs.
• It exerts no negative influence on the surface quality of white (TiO2) m-LLDPE films.
The new UV absorber Uvinul® S-Pack provides even better protection from UV radiation for sensitive substances such as vitamins and colorants in PET bottles. Unlike traditional UV absorbers, it also absorbs long-wave UV light, thereby extending the shelf life of the contents. Another benefit is that its blue fluorescence prevents any yellowing of the plastic. This means PET packaging can also be used where an attractive packaging is just as important as the UV protection of the contents.
DuPontTM�s Light Stabilizer 210 uses extremely small particles of titanium dioxide (TiO2) to efficiently absorb ultraviolet light, protecting plastic and anything it covers from the sun's damaging rays. This is the first in a family of products based on breakthrough DuPont titanium dioxide process technology. It is an additive designed for use in plastics to help protect products from cracking, fading and other types of solar degradation. Potential applications include sporting goods, outdoor furniture, fabrics and carpet fibers - virtually any plastic product that will be exposed to sunlight. It also can be used in plastic films and sheeting to protect plants in greenhouses or packaged goods from UV light. In testing, this product blocked twice as much ultraviolet light as several classes of competitive products. It works by absorbing ultraviolet rays and changing them into small amounts of heat which dissipate quickly without damaging the structure of plastic. The key performance advantage of the new light stabilizer is that its extremely small particle size provides much more surface area for UV absorption.
Eastman�s Vitiva PET PC715 is an exceptionally clear PET polyester that contains a UV light protection package chemically bound to the backbone of the polymer. This non-extractable UV inhibitor absorbs damaging wavelengths of light, protecting the contents of the package. In addition, Vitiva PET allows brand owners to achieve uniquely shaped containers with extraordinary clarity thereby showcasing the contents of the package. Voridian, the world's largest supplier of PET resins for packaging, has launched a new PET resin that provides ultraviolet (UV) light protection for food and beverage products. It contains an FDA-approved UV absorber that protects delicate colours, flavours, vitamins and nutrients in custom packaging applications. It also offers significant processing advantages. The resin is capable of efficient blow-molding output rates and can accommodate a number of bottle production stages. The resin's UV inhibitor produces no plate out on molds or dryers. Using existing injection-molding and/or blow-molding tooling, it requires no extra capital investment in machinery or tooling. It can also be used as a drop-in replacement for standard PET. Vitiva PET has been specifically designed to combine UV protection and high clarity in a single PET packaging material. The polymer is capable of producing sharp, consistent colours in packaging applications. The material also allows for significant bottle design flexibility and crisp definition on embossments and logos.
Nanophase Technologies Corp offers zinc oxide nanoparticle additive called 'NanoArc,' which provides UV protection without affecting transparency, gloss, color, or physical properties. NanoArc is a Tin Oxide nanoparticle additive can be incorporated in clear film and sheet to absorb IR but not visible light. It provides this benefit by absorbing energy in the near-IR region and reflecting energy at longer IR wavelengths, while maintaining excellent transparency in the visible region. The incorporation of NanoArc ATO into surface coatings is an effective means of managing radiant heat without adversely impacting the optical clarity or other desirable physical properties of the article on which it is applied. Nanoparticles are available as coated dry powders wherein the material is treated to impart specific surface functionality to the particles, such as hydrophobicity. The technology is designed for individual nanoparticle coating and as such prevents the formation of irreversible agglomerates. The coating can be tailored to accommodate a range of surface functionality/reactivity, thereby providing the optimum compatibility with individual applications.
INVISTA has created Polyclear® ProtectTM PET 2201U polymer - a polyester polymer designed to protect packaged food and beverages against ultraviolet rays. It reduces the amount of UV light passing through the bottle or container which can degrade flavoring, vitamin content, fragrance and color of the package contents. The UV protection is embedded directly into the PET polymer to eliminate production variability and help the product retain its functional characteristics during the bottle-making process. It can be processed on standard manufacturing lines and does not require new capital expenditure for additional processing equipment. This packaging resin also complies with the Federal Food, Drug and Cosmetic Act for certain food contact applications and can be reclaimed in available PET recycling chains. The key benefits that define the polymer are:
• Excellent thermal stability for heat-set, hot-fill and pasteurized applications resulting in an improved container for greater flexibility in filling
• Brilliant clarity and excellent UV protection that can extend product shelf-life
• Outstanding processability and efficiency in bottle manufacturing
• No need for machine-side mixing that is common for other UV-protectant additives
• Avoids the problems and inconsistencies that accompany poor blending in machine-side additives
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Complete Herbert Olbrich cushion vinyl flooring line

Complete Herbert Olbrich cushion vinyl flooring line