The miscibility of poly(d l-lactide) and poly(ε-caprolactone) (PDLLA/PCL) blends in a wide composition range was studied by the thermally stimulated depolarization currents technique by following the local and segmental dielectric relaxations changes as the blend composition is varied. The PCL primary relaxation is slightly shifted to higher temperatures as the PDLLA content increases, thus demonstrating the existence of a rich PCL phase and partial miscibility with PDLLA. Wide-angle X-ray scattering showed that neat PDLLA was amorphous, as expected for a sample with 12 mol % d-lactide isomer; nevertheless, the presence of 3D order was detected in the PDLLA that was melt blended with PCL. Differential scanning calorimetry also evidenced chain interaction by the decrease in the melting and crystallization temperatures as well as in the PCL crystallization kinetics which becomes slower in the presence of increasing amounts of PDLLA.

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A positive-tone, aqueous base soluble, polynorbornene (PNB) dielectric formulation has been developed. The photolithographic solubility switching mechanism is based on diazonaphthoquinone (DNQ) inhibition of PNB resin functionalized with pendent fluoroalcohol and carboxylic acid substituents. The optical contrast (at 365 nm) was found to be 2.3. The maximum height-towidth aspect ratio of developed line and space features was 3 : 2. The sensitivity, D 100 , of a formulation containing 20 pphr of DNQ photoactive compound (PAC) was calculated to be 408 mJ cm À2 . The effects of the PAC molecule structure on miscibility and dissolution of the photosensitive films in aqueous base developer were studied. The effect of the monomer composition of the PNB polymer on the dissolution rate of the formulated PNB resin was evaluated. A unique dissolution and swelling behavior was observed. The effect is attributed to a copolymer synthesized with two monomers each of which is susceptible to deprotonation in aqueous base. FTIR measurements showed that the pure PNBFA has a small percentage of free hydroxyl groups, which did not change appreciably by the addition of PAC to the mixture.The polymers used in this study were homopolymers or copolymers of functionalized PNB monomers. 10 Functionalized monomers, a norbornene fluoroalcohol (NBFA) and a norbornene carboxylic acid (NBCBA), impart solubility in aqueous base. The NBCBA functionality also provides sites for polymer crosslinking with small-molecule, multifunctional epoxy additives.

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