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Syndiotactic polystyrene (SPS) has a unique crystalline phase, named ε, that has a tubular cavity inside. We connected these cavities by optimizing the solvent used to process the films and to polymerize aniline within these channeling cavities only by immersing the films in degassed hydrochloric acid solutions of ammonium persulfate. We succeeded in fixing pentameric to octameric oligoaniline in the cavities of the SPS ε crystalline phase. This is a new and sophisticated preparation method of polymer composites between SPS and linear oligomers/polymers within its longconnected tubular cavities.

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The morphology of syndiotactic polystyrene (SPS) with several typical fragrant molecules is studied to clarify what solvent conditions can produce SPS gel, which is expected to be a material that can release fragrance for a long period of time. Eight fragrant solvent molecules are employed to dissolve SPS at high temperatures and the morphologies they show after cooling are checked. Their morphologies can be divided into three: a gel with a three‐dimensional network consisting of a fibrillar structure having the SPS δ phase, a paste‐like state consisting of a non‐lamellar spherulitic structure having the SPS γ phase, and a sherbet‐like state consisting of a lamellar structure having the SPS β phase. Finally, the necessary conditions of a solvent to be able to form an SPS gel turn out to be its molecular size being less than ≈160 Å3 and its Fedors' solubility parameter having a value whose gap from SPS is less than 1.5 (cal/cm3)1/2.magnified image

Curdlan is a polysaccharide that is expected to work as a gene carrier. We synthesized chemically cross-linked Curdlan (CCC) gel and examined its characterization. CCC gels were swollen with alkaline water over pH ∼10.2, but shrunk with acid and neutral water. Swelling ratios of the present CCC gels with water were found to be 45 times at the most and dependent on the fraction of cross-linker reagent. These volume phase transition gels that are sensitive to pH are useful and ecological as a biocompatible and biodegradable material.