Styrene-co-maleic

A photosensitive composition, consisting of an aromatic azide compound (4,4 -diazidodi-phenyl methane) and a resin matrix (poly (styrene-co-maleic acid half ester)), has been developed and evaluated as a negative deep UV resist for high resolution KrF excimer laser lithography. Solubility of this resist in aqueous alkaline developer decreases upon exposure to KrF excimer laser irradiation. The alkaline developer removes the unexposed areas of this resist. 

The photosensitive azide compound was 4,4 -diazidodiphenyl methane (m.p. 44.0 t). The poly(styrene-co-maleic acid half ester) was used as a resin matrix. 

Figure 1. Chemical structures of (a) 4,4 -diazidodi-phenyl methane and (b) poly(styrene-co-maleic acid half ester).

A negative deep UV resist, consisting of a photosensitive 4,4 -diazidodiphenyl methane and a poly-(styrene-co-maleic acid half ester) resin, has been found to meet the requirements needed for KrF excimer laser lithography. 

Fig. 1 Chemical structures of the polymers commonly used for preparation of beads poly (styrene-co-maleic acid) (=PS-MA) poly(methyl methacrylate-co-methacrylic acid) (=PMMA-MA) poly(acrylonitrile-co-acrylic acid) (=PAN-AA) polyvinylchloride (=PVC) polysulfone (=PSulf) ethylcellulose (=EC) cellulose acetate (=CAc) polyacrylamide (=PAAm) poly(sty-rene-Wocfc-vinylpyrrolidone) (=PS-PVP) and Organically modified silica (=Ormosil). PS-MA is commercially available as an anhydride and negative charges on the bead surface are generated during preparation of the beads...

Figure 3. GPC molecular weight data for poly-(styrene-co-maleic anhydride) copolymerized in acetone...

Figure 5. Molecular weight data for poly(styrene - co -maleic anhydride) copolymerized in benzene. Gel permeation chromatographic data obtained from THF solution containing hydroquinone...

As shown by the gel permeation chromatograph in Figure 6, the average molecular weight of poly(styrene-co-maleic anhydride) obtained by adding the macroradical to a benzene solution of the monomers was over 250,000. No copolymer was obtained under comparable conditions in the absence of the macroradicals. Attempts to use these macroradicals to produce copolymers in an acetone solution were unsuccessful. 

The formation of block copolymers from styrene-maleic anhydride and acrylic monomers was also indicated by pyrolytic gas chromatography and infrared spectroscopy. A comparison of the pyrograms of the block copolymers in Figure 7 shows peaks comparable with those obtained when mixtures of the acrylate polymers and poly(styrene-co-maleic anhydride) were pyrolyzed. A characteristic infrared spectrum was observed for the product obtained when macroradicals were added to a solution of methyl methacrylate in benzene. The characteristic bands for methyl methacrylate (MM) are noted on this spectogram in Figure 8. 

Soluble carriers include antibodies and soluble synthetic polymers such as poly(hydroxypropyl methacrylate), poly(lysine), poly(aspartic acid), polyvinylpyrrolidone), poly(N-vinyl-2-pyrrolidone-co-vinylamide) and poly (styrene co-maleic acid/anhydride). 

The cytotoxic neocarzinostatin (NCS) is a small protein (Mw 12 kD) associated with a low molecular weight chromophore. NCS is rapidly cleared by the kidney and its cytotoxicity is non-cell specific. To modify its disposition, two poly(styrene-co-maleic acid anhydride) copolymers (Mw 1,500) have been coupled to one molecule of NCS, to give styrene-maleic-anhydride-neocarcinostatin (SMANCS) systems. 

Preparation of Poly(Styrene-co-Maleic Anhydride-b-Styrene-co-Acrylonitrile)... 

Heinen W, Wenzel CB, Rosenmoeller CH, Mulder FM, Boender GJ, Lugtenburg J, de Groot HJM, Van Duin M, Klumperman B (1998) Solid-state NMR study of miscibility and phase separation in blends and semi-interpenetrating networks of 13C-labeled poly(styrene-co-acrylonitrile) and poly(styrene-co-maleic anhydride). Macromolecules 31 7404-12. 

The polymer microstructure based on triad intensities in pyrolysates has been evaluated for poly(styrene-co-butyl acrylate), poly(styrene-co-methyl methacrylate), poly(vinyl chloride-co-vinylidene chloride), poly(styrene-co-maleic anhydride), and for chlorinated polyethylene considered as a copolymer of polyethylene and vinyl chloride [30]. 

Among the copolymers of styrene that have practical applications is poly(styrene-co-maleic anhydride) [71]. The pyrogram of a sample of poly(styrene-co-maleic anhydride), CAS 9011-13-6, with 7% wt maleic anhydride and = 224,000 is given in Figure 6.2.8. The pyrolysis was done at 600° C in He with separation of a Carbowax column and MS detection, similarly to other polymers discussed in this book (see Table 4.2.2). 

Figure 6.2.8. Result for a Py-GC/MS analysis of poly(styrene-co-maleic anhydride) 7% wt. maleic anhydride, M = 224,000. Pyrolysis done at 60(f C in He, with the separation on a Carbowax type column.

Mu Y et al (1999) Bioconjugation of laminin peptide YIGSR with poly(styrene co-maleic acid) increases its antimetastatic effect on lung metastasis of B16-BL6 melanoma cells. Biochem Biophys Res Commim 255 75-79... 

Fig. 17 Structural representation of the anti-tumor agent (SMA)2NCS, a block copolymer of poly[styrene-co-(maleic anhydride)] coupled to the protein neocarzinostatin. By increasing the molecular weight of the protein, a passive form of tumor targeting occurs due to the increased vascular permeability associated with tumors. Reprinted with permission from [9]. Copyright 2003 Wiley. Adapted from [111]...

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