Dye-polymer solutions

The Dye-in-Polymer concept was first proposed and reduced to practice in our laboratory (12). It involves the ablative marking with an appropriate laser, of a polymer film containing a dissolved dye. The dye-in-polymer film can be easily prepared by spin-coating a dye/polymer solution onto a reflective substrate. The structure of the DIP recording medium is shown in Figure 8. 

A variety of organic-polymeric-based materials have been investigated for optical recording, including dyes (pigments), dye (pigment)-polymer composites, dye-polymer solutions, and polymer-metal-layered or particulate structures. In all instances, the light absorption function is provided by the dye or metal, and the polymer serves the role of binder and film former. 

Law and Johnson (22, 29) published the most detailed analysis of the role of the polymer chemical and physical properties on the sensitivity and performance of dye-polymer solutions. Their key results are collected and summarized in Table 7.3. They investigated addition- and condensation-type polymers and probed the effect of physical properties such as glass transition... 

Nickel also has been used as a dye site in polyolefin polymers, particularly fibers. When a nickel compound, eg, the stearate or bis(p-alkylphenol) monosulfide, is incorporated in the polyolefin melt which is subsequently extmded and processed as a fiber, it complexes with certain dyes upon solution treatment to yield bright fast-colored fibers which are useful in carpeting and other appHcations (189). Nickel stearate complexing of disperse mordant dyes has been studied (190). 

Both acrylic acid and methacrylic acid polymerise to give water soluble hard resins. The viscous solutions so formed have been used as emulsifying agents, adhesives and as thickening agents for inks and dyes. Polymers of esters of these acids are of greater commercial importance. Esters can be prepared from cyanhydrins by reaction with an alcohol ... 

PVA). In methanol, an intense monomer absorption maximum is located at 870 nm. In the polymer film, at a dye polymer loading ratio of 1 to 5, the 870 nm solution maximum is broadened and split into two bands due to aggregation, centered at 700 and 950 nm respectively. However, no evidence of microcrystal formation in the film was detected upon examination with an optical microscope and thus, if present, microcrystals are less than 1000 A in diameter. 

Whether the dye is inert or whether it generates some time dependent signal by itself (e.g. through a photoreaction or transition into a triplet state) is easily checked from a measurement of the dyed solvent without polymer solute. 

The polymer solution is spotted on a solid support or dispensed in the single wells of a microwell plate. After drying, the fluorescent dyes can be immobilized on these matrices. Direct spotting and drying of a mixed polymer/luminophore cocktail can be an alternative. 

It has been shown that methylene blue binds to DNA in a manner similar to that of acridine orange, with the intercalated solute being coplanar with the base pairs at low dye/polymer ratios and low ionic strengths [89]. The induced CD data indicated the existence of two origins for the observed chirality. At low ratios of dye/polymer, the CD is... 

The polarization of free dye dissolved in a solution of the unconjugated polymer is low for dilute polymer solutions but as the concentration of polymer is increased the value of p approaches that of the conjugated plastic. That is, the relaxation time of the fluorescent species in the hard plastic is the same whether or not it is chemically attached to polymer chain (15). 

---