The present invention provides a polyrotaxane which exhibits more excellent compatibility with various solvents, while having good processability. The present invention provides a polyrotaxane which is obtained by arranging blocking groups on both ends of a pseudopolyrotaxane, wherein a linear molecule passes through the opening of a circular molecule in a skewering manner, for the purpose of preventing elimination of the circular molecule. This polyrotaxane has a group which has a chain that is formed by having the circular molecule have a propyleneoxy repeating unit; and this polyrotaxane is soluble in a polyalkyleneoxy polyol, which has a number average molecular weight of 1,000 or more, at room temperature.

A method for purifying a specific trityl group-containing monodispersed polyethylene glycol from a mixture containing the trityl group-containing monodispersed polyethylene glycol and a specific ditritylated impurity. The method includes performing steps (A), (B) and (C). Step (A): a step of esterifying the hydroxyl group of the trityl group-containing monodispersed polyethylene glycol by a specific method; Step (B): a step of extracting the esterified compound by a specific method; and Step (C): a step of hydrolyzing the esterified compound to obtain the trityl group-containing monodispersed polyethylene glycol.

A method for purifying a specific trityl group-containing monodispersed polyethylene glycol from a mixture containing the trityl group-containing monodispersed polyethylene glycol and a specific ditritylated impurity. The method includes performing steps (A), (B) and (C). Step (A): a step of esterifying the hydroxyl group of the trityl group-containing monodispersed polyethylene glycol by a specific method; Step (B): a step of extracting the esterified compound by a specific method; and Step (C): a step of hydrolyzing the esterified compound to obtain the trityl group-containing monodispersed polyethylene glycol.

Membranes permeable to an analyte may overlay the active sensing region of a sensor to limit the analyte flux and improve the response linearity of the sensor. Temperature variation of the analyte permeability can be problematic in some instances. Polymeric membrane compositions having limited variation in analyte permeability as a function of temperature may comprise: a polymer backbone comprising one or more side chains that comprise a heterocycle; and an amine-free polyether arm appended, via an alkyl spacer or a hydroxy-functionalized alkyl spacer, to the heterocycle of at least a portion of the one or more side chains.

A process for preparing non-naturally-occurring defined monomer sequence polymers is provided, and in which a high degree of synthetic control is obtained by the use of solvent resistant diafiltration membranes. Also provided is a process for separating non-naturally-occurring defined monomer sequence polymers from synthetic by-products or excess reagents using solvent resistant diafiltration membranes, and a use of a solvent resistant diafiltration membrane in processes for preparing and separating non-naturally-occurring defined monomer sequence polymers.

Disclosed are a multifunctionalized polyethylene glycol derivative and a preparation method therefor. The derivative has an H-shaped structure as represented by formula (1) and comprises one linear core LPEG and four PEG branch chains, where n.sub.1, n.sub.2, n.sub.3, and n.sub.4 respectively are the degrees of polymerization of the branch chains, U.sub.1 and U.sub.2 are trivalent branching groups connecting the core LPEG to two of the PEG branch chains, F.sub.1 and F.sub.2 contain a functional group or a protected form R.sub.01 thereof and may or may not contain a branched group G, correspondingly, the number of R.sub.01 is one or more, F.sub.1 and F.sub.2 are either identical or different, any one linking group in the molecule or any linking group formed with an adjacent heteroatom group can either remain stable or be degraded, and any one PEG segment in the molecule is discretely polydispersed or monodispersed. The multifunctional polyethylene glycol is flexible and diverse in terms of branch structures and the lengths of branching arms, has various parameters and performance indicators that are adjustable and easy to control, and has a broad applicability.

The additive for high-purity copper electrolytic refining of the present invention is an additive which is added to a copper electrolyte in electrolytic refining for high-purity copper and is formed of a non-ionic surfactant that includes a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group, in which a dispersion term dD of the Hansen solubility parameters satisfies 10≦dD≦20, a polarity term dP of the Hansen solubility parameters satisfies 6≦dP≦9, and a hydrogen bonding term dH of the Hansen solubility parameters satisfies 9≦dH≦11.

The additive for high-purity copper electrolytic refining of the present invention is an additive which is added to a copper electrolyte in electrolytic refining for high-purity copper and is formed of a non-ionic surfactant that includes a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group, in which a dispersion term dD of the Hansen solubility parameters satisfies 10≦dD≦20, a polarity term dP of the Hansen solubility parameters satisfies 6≦dP≦9, and a hydrogen bonding term dH of the Hansen solubility parameters satisfies 9≦dH≦11.

The additive for high-purity copper electrolytic refining of the present invention is an additive which is added to a copper electrolyte in electrolytic refining for high-purity copper and is formed of a non-ionic surfactant that includes a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group.

The additive for high-purity copper electrolytic refining of the present invention is an additive which is added to a copper electrolyte in electrolytic refining for high-purity copper and is formed of a non-ionic surfactant that includes a hydrophobic group containing an aromatic ring and a hydrophilic group containing a polyoxyalkylene group.