TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Crosslinking Agent: The crosslinking agent is chosen from cyanuric chloride, trimesoyl chloride, terephthaloyl chloride, epichlorohydrin, dibromo benzene, glutaraldehyde, phenylene diisocyanate, divinyl sulfone, 1-1'-carbonyl diimidazole and alkoxysilanes. Preferred Ionic Liquid: The ionic liquid is non-volatile and has melting point of more than -100degreesC. The ionic liquid is compound chosen from 1,3-dialkyl imidazolium salts, N-pyridinium salts, tetraalkylammonium salts and tetralkylphosphonium salt.    TECHNOLOGY FOCUS - POLYMERS - Preferred Polymer: Portion(s) of the polymer is cross-linked physically and/or chemically. The maximum swelling rate of the material in ionic liquid from dried condition of the material not containing ionic liquid, is 1.1 or more by weight conversion, when the weight of material in dried condition is set to 1. The maximum expansion ratio of the material containing ionic liquid in saturation state is 5% or more. The Young's modulus of material containing ionic liquid in saturation state is 100000 Pa or less. The weight ratio of polyrotaxane to polymer is more than 1/1000. The polymer has photocrosslinking group chosen from hydroxyl, amino, carboxyl, epoxy, vinyl and/or thiol group in principal chain or side chain. Alternately the polymer is polyrotaxane (II) having sealing group arranged at both ends of linear molecule (II) which includes cyclic molecule (II) which is not detached from the linear molecule (II). Portion(s) of the polyrotaxane (I) and polyrotaxane (II) are bonded via the cyclic molecule (I) and/or (II). The linear molecule (I and/or II) is chosen from polyethylene glycol, polyisoprene, polyisobutylene, polybutadiene, polypropylene glycol, polytetrahydrofuran, poly-dimethyl siloxane, polyethylene and polypropylene. Molecular weight of linear molecule (I and/or II) is 10000 or more. The sealing group is chosen from dinitro phenyl groups, cyclodextrin, adamantane groups, trityl, fluorescein, pyrenes, substituted benzene, optionally substituted polynuclear aromatics, and/or steroids. The linear molecule (I and/or II) is optionally substituted with cyclodextrin molecule chosen from alpha-cyclodextrin, beta-cyclodextrin, gamma-cyclodextrin and their derivatives, preferably alpha-cyclodextrin. The linear molecules (I and/or II) are polyethyleneglycol. The amount of cyclic molecules (I and/or II) included in the linear molecules (I and/or II), is 0.001-0.6, when the amount of linear molecules (I and/or II) is 1. The polymer and cyclic molecule of polyrotaxane are bonded by cross-linking agent having molecular weight of less than 2000. When the swelling rate and storage elastic modulus of the comparison material using dimethyl sulfoxide instead of ionic liquid is set to 1, the swelling rate and storage elastic modulus of the material are 0.1-10 and 0.1-15 respectively. Preferred Process: Alternately, the cyclic molecule (I) and linear chain molecule (I) are mixed and the cyclic molecule is included in the linear molecule. Sealing group is arranged at both ends of linear molecule to prepare polyrotaxane (I), and the cyclic molecule is not detached from linear molecule. The monomer which comprises polyrotaxane and polymer are mixed and monomer is polymerized to form polymer. Portion(s) of the polymer and polyrotaxane are combined via the cyclic molecule to obtain conjugate. The above processes are performed in ionic liquid or the conjugate obtained above is immersed in ionic liquid, to obtain the material. The conjugate preparation is carried out in dimethyl sulfoxide solvent, and conjugate containing dimethyl sulfoxide is immersed in water. The dimethyl sulfoxide is then substituted by water. The conjugate material is immersed in mixed solvent of volatile solvent and ionic liquid, and water is substituted by mixed solvent. The conjugate containing mixed solvent is immersed in ionic liquid and the material is obtained. EXAMPLE - Crosslinked polyrotaxane was prepared by manufacture of crosslinked polyrotaxane of patent 3475252. Polyethylene glycol having molecular weight of 35000 (6g), alpha-cyclodextrin (24g), adamantane amine (0.32g) and 1,1'-carbonyl diimidazole, were mixed. The crosslinked polyrotaxane was prepared in dimethylsulfoxide and solvent was substituted by water. The mixture was dried using silica gel. The dried crosslinked polyrotaxane was immersed in 1-butyl-3-methyl imidazoliumchloride (ionic liquid) for 2 days or more at 80degreesC. Crosslinked polyrotaxane swollen with ionic liquid was obtained. The polymer had swelling rate of 17 times with respect to dry weight. The maximum expansion rate of cross linked polyrotaxane in swollen state at room temperature was 55% and Young's modulus was 11500 Pa.