Summary: A series of methacrylate copolymers containing polyhedral oligomeric silsesquioxane (POSS) was synthesized from the free radical copolymerization of methacrylic acid, methyl methacrylate, and isobutyl propylmethacryl polyhedral oligosilsesquioxanes, and then were modified with glycidyl methacrylate to serve as negative‐type photoresists. The UV/Vis spectroscopy reveals that the incorporation of POSS moiety into the copolymer results in a slight decrease in transparency from 99 to 92.5% (at wavelength = 365 nm). The photosensitivity in terms of resist sensitivity (D n0.5), contrast (γ), and photopolymerization rate are significantly increased with increase in the POSS content. In addition, the induction time is reduced from 0.520 to 0.515 min after incorporating the POSS unit based on photo‐DSC analyses. These observed results can be rationalized as due to hydrogen bonding interactions between siloxane and hydroxyl groups in copolymers which tend to attract the methacrylate double bonds surrounding POSS units to crosslink, thereby enhancing the photopolymerization rate and sensitivity. We further evaluate the lithographic property of a photoresist under a collimated exposure.

Mono-polyhedral oligomeric sillsesquioxane-end capped poly(e-caprolactone) (mPPCL) can form inclusion complexes (ICs) with a-and c-cyclodextrins (CDs) but not with b-CD. These CD ICs have been characterized with X-ray diffraction, solid-state 13 C cross-polarization/magic-angle-spinning NMR spectroscopy, 1 H NMR spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy. The poly(e-caprolactone) (PCL) chain of mPPCL is included within the channel provided by the CDs to form a columnar, crystalline structure. The PCL/CD ratios determined by 1 H NMR spectroscopy for the ICs with a-or c-CDs are higher than the stoichiometries because of the steric hindrance of the bulky polyhedral oligomeric silsesquioxane chain end and result in a fraction of the e-caprolactone units free from complexation with the CDs. On the basis of these analyses, we propose some possible structures for these CD/mPPCL ICs. V V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 125-135, 2007 a Degradation temperature for free CDs and mPPCL (taken from TGA curves showing a 5% mass loss at each step of degradation under nitrogen). b Degradation temperature for the components in the CD/mPPCL complexes (taken from TGA curves showing a 5% mass loss at each step of degradation under nitrogen).

No abstract