Photo stability acrylics

The photochromism of the acrylate-substituted spiroindolinobenzothiopyran 605 is characterized by the unusual stability of the ring-opened colored species [Amax 670 nm, (acetone)] (Equation 204) <2002JOC533> other photo-chromic spiroindolinobenzothiopyrans have been incorporated in electrostatic toner compositions <1998LJSP5759729>. 

Miscellaneoiis Polymers.—Allen et al. have studied the post-cured photo-oxidative stability of di- and tri-acrylate resins having structures (9) or (10)... 

It is known that the advantages of imprinted ormosils (organically modified silanes) over acrylic-based MIPs are their chemical stability, the high thermal stability of sol-gel materials, synthesis in mild temperature conditions, optical transparency, photo-, electro- and chemical stability, all properties that made these materials ideal for use in optical sensing approaches, particularly in aqueous samples.48 50 Although... 

The comonomer used for copolymerization with tetramethyl-4-piperidyl methacrylate influences the observed light stabilizing effect in blends with PP [302], The best efficiency was imparted by copolymers with styrene and alkyl acrylates. The most efficient copolymer with styrene was also tested in photo-oxidized cis- 1,4-polybutadiene and was found to be less efficient than 35a. 

Chem. Descrip. 2-(2-Hydroxy-W-octylpheriyl)-benzotriazole CAS 3147-75-9 EINECS/ELINCS 221-573-5 Uses UV absorber/lt. stabilizer for polymeric systems ind. polyester, PVC, styrenics, acrylics, PC, and polyvinyl butyral for ind. molding, sheef, and glazing materials for window, marine, and auto applies., coatings, photo prods., sealants, and elastomeric materials stabilizer for fo grade polymers... 

A gel electrolyte consists of an ion conducting polymer, such as polyoxyethylene or a polymer with polyoxyethylene segment, and an ion source. Hexafluorophosphate or tetrafluoroborate salts of lithium are commonly employed as the ion source. Other common components of the gel are liquid electrolytes like ethylene carbonate or propylene carbonate, both of which are used to increase the overall ion conductivity. Cross-linking agents, such as photo cross-linked acrylates or polyurethanes, can be incorporated to improve the mechanical stability of gel electrolytes. 

This system is claimed to possess good thermal stability and high photochemical driving force. Upon irradiation, an electron transfer reaction between excited dye and iodonium salt leads to photo bleaching of the squarylium dye and generation of active radicals. The results obtained indicate that squarylium dye and iodonium salt systems will effectively initiate visible light photopolymerization and photocrosslinking of acrylic esters. ... 

Photo-triggered ring opening of 2//-azirines is a well-known reaction to produce pyrrolines [8, 71]. Padwa and co-workers showed that photoirradiation of azirines with a mercury arc lamp (450 W) equipped with Vycor filter generated the reactive nitrile ylide intermediate (72), which can be stabilized by the phenyl substituents. The nitrile ylide (72) then reacts with the electron-deficient olefins (73) such as acrylate and acrylonitrile in a cycloaddition reaction to form A -pyrrolines (74) (Scheme 10) [8]. Steenken and co-workers studied reaction kinetics of azirines with dipolarophiles as well as nucleophiles such as alcohols [72]. They showed that the reaction rate depends on the azirine substituents, the nucleophilicity of the reactant and the acidity of the alcohol. 

In the 1950s, Feller (1972) showed that fluorinated acrylics had even higher stability than those currently available. These have been extensively researched for use on external stone surfaces (see Table 8.2 for typical examples). They cannot be used as homopolymers, because they have relatively high Tg values and dissolve in few solvents. As has been similarly shown with the parent polymers, the distribution of the fluorine substitutents appears to be important in determining the photo-oxidative stability of the polymer (Signori et al., 2006). However, suitable polymers have yet to be developed that meet the other requirements of this usage (Toniolo et al., 2002). 

AQ dyes are used for a broader spectrum of resins than that of the azo dyes. They are heavily used in styrene, ABS, SAN, polycarbonate, acrylics, cellulosics, polyesters etc. and are well known for excellent weatherability in the transparent mode such as red taillights, but in tint applications the light stability is greatly reduced. Heat, photo and chemical stability vary considerably as the pendants on the base AQ structure are substituted. Awareness of these differences is essential in color formulating. Most AQ dyes are not recommended for polyamide applications as these resins react with amine pendants and can remove the color. We are... 

Chiantore O, Lazzari M (2001) Photo-oxidative stability of pataloid acrylic protective polymers. Polymer 42 17-27... 

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