Disclosed are a polymer having a narrow molecular weight distribution prepared by living radical and a polymer manufacturing method comprising a step of performing living radical polymerization using 0.005 to 0.5 parts by mass of an oxygen radical scavenger per 100 parts by mass of a radical polymerizable monomer.

Disclosed are a polymer having a narrow molecular weight distribution prepared by living radical and a polymer manufacturing method comprising a step of performing living radical polymerization using 0.005 to 0.5 parts by mass of an oxygen radical scavenger per 100 parts by mass of a radical polymerizable monomer.

A method of preparing an acrylonitrile-based copolymer for a carbon fiber. The method includes: preparing a reaction solution including a (meth)acrylonitrile-based monomer and a first reaction solvent; adding a first portion of a radical polymerization initiator to the reaction solution to initiate polymerization; and adding a second portion of the radical polymerization initiator to the reaction solution when a polymerization conversion ratio is between 70 to 80%.

A method of preparing an acrylonitrile-based copolymer for a carbon fiber. The method includes: preparing a reaction solution including a (meth)acrylonitrile-based monomer and a first reaction solvent; adding a first portion of a radical polymerization initiator to the reaction solution to initiate polymerization; and adding a second portion of the radical polymerization initiator to the reaction solution when a polymerization conversion ratio is between 70 to 80%.

The present invention provides a polymer-based piezoelectric composite material from which a piezoelectric film capable of outputting a higher sound pressure is obtained in a case of using a piezoelectric speaker, a piezoelectric film formed of the polymer-based piezoelectric composite material, and a piezoelectric speaker and a flexible display which are formed of the piezoelectric film. The polymer-based piezoelectric composite material of the present invention is a polymer-based piezoelectric composite material including a polymer matrix which contains a polymer containing a group represented by Formula (1), and piezoelectric particles.

*-L.sup.1-CR.sup.1R.sup.2—CN  Formula (1) In Formula (1), L.sup.1 represents a divalent linking group excluding a divalent aliphatic hydrocarbon group. R.sup.1 and R.sup.2 each independently represent a hydrogen atom, an alkyl group, or an aryl group.

The present invention provides a polymer-based piezoelectric composite material from which a piezoelectric film capable of outputting a higher sound pressure is obtained in a case of using a piezoelectric speaker, a piezoelectric film formed of the polymer-based piezoelectric composite material, and a piezoelectric speaker and a flexible display which are formed of the piezoelectric film. The polymer-based piezoelectric composite material of the present invention is a polymer-based piezoelectric composite material including a polymer matrix which contains a polymer containing a group represented by Formula (1), and piezoelectric particles.

*-L.sup.1-CR.sup.1R.sup.2—CN  Formula (1) In Formula (1), L.sup.1 represents a divalent linking group excluding a divalent aliphatic hydrocarbon group. R.sup.1 and R.sup.2 each independently represent a hydrogen atom, an alkyl group, or an aryl group.

A cyanoacrylate composition with thermoplastic polyurethane, formulated as a non-flowable soft solid or semi solid mass, for example in stick form, is reported.

A cyanoacrylate composition with thermoplastic polyurethane, formulated as a non-flowable soft solid or semi solid mass, for example in stick form, is reported.

A cyanoacrylate composition with thermoplastic polyurethane, formulated as a non-flowable soft solid or semi solid mass, for example in stick form, is reported.

A cyanoacrylate composition with thermoplastic polyurethane, formulated as a non-flowable soft solid or semi solid mass, for example in stick form, is reported.