Disclosed are a polyol composition using carbon dioxide, a method for preparing a polyurethane foam using the polyol composition, and a polyurethane foam prepared using the method. A method for preparing a polyurethane foam includes reacting isocyanate with a polyol composition containing a polyol compound having a synthetic polyol containing carbon dioxide, a chain extender, and a foaming agent.

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.

The present invention relates to a novel process for the synthesis of (per)fluoropolyether polymers, to certain novel (per)fluoropolyether polymers. The present invention also relates to the use of the (per)fluoropolyether polymers thus obtained as intermediate compounds for the manufacture of further polymers suitable for use as lubricants, notably for magnetic recording media (MRM).

A process for preparing a low-molecular weight fluoropolyether containing an acid fluoride by decomposing a triflate or trifluoroacetate of a fluoropolyether having a hydroxyl group in the presence of a Lewis acid.

A process for preparing a low-molecular weight fluoropolyether containing an acid fluoride by decomposing a triflate or trifluoroacetate of a fluoropolyether having a hydroxyl group in the presence of a Lewis acid.

A fluorine-containing ether compound represented by Formula (1) is provided.

R.sup.1—O—R.sup.2—CH.sub.2—R.sup.3—CH.sub.2—R.sup.4—R.sup.5  (1)

(in the formula, R.sup.3 is a perfluoropolyether chain; R.sup.1 is an alkenyl group having 2 to 8 carbon atoms or an alkynyl group having 3 to 8 carbon atoms; R.sup.2 and R.sup.4 are each independently a divalent linking group having one or more hydroxyl groups; and —R.sup.5 is a group represented by Formula (2) shown below.)

—O—(CH.sub.2).sub.g—N—R.sup.6R.sup.7  (2)

(in the formula, g is an integer of 2 or 3; R.sup.6 and R.sup.7 are the same or different saturated aliphatic groups; and R.sup.6 and R.sup.7 may form a ring structure together with a nitrogen atom.)

An article of manufacture. The article of manufacture includes a ring-opened lactide copolymer. The ring-opened lactide copolymer is formed in a process that includes reacting a functionalized lactide monomer with a BPA-derived monomer. The reaction forms a lactide copolymer, which is reacted to form the ring-opened lactide copolymer.

An article of manufacture. The article of manufacture includes a ring-opened lactide copolymer. The ring-opened lactide copolymer is formed in a process that includes reacting a functionalized lactide monomer with a BPA-derived monomer. The reaction forms a lactide copolymer, which is reacted to form the ring-opened lactide copolymer.

A method for producing a multi-arm type polyethylene glycol derivative, which includes carrying out the following in order: Step (A): protecting an even number of hydroxyl groups, while leaving only the hydroxyl group at the 1-position of a polyhydric alcohol having an odd number of hydroxyl groups, other than the hydroxyl group at the 1-position by cyclic benzylidene acetalization, Step (B): linking two molecules of the compound obtained in step (A) to a compound for introducing a specific linker by etherification reaction, Step (C): deprotecting the cyclic benzylidene acetal structure at the terminal of the compound obtained in step (B), Step (D): polymerizing 3 to 600 mol of ethylene oxide to each hydroxyl group of the compound obtained in step (C) to obtain a multi-arm type polyethylene glycol derivative, and Step (E): functionalizing the hydroxyl group at the terminal of the multi-arm type polyethylene glycol derivative obtained in step (D).