The present invention provides a composition of a polyethylene glycol maleimide derivative and a polymerization inhibitor. In particular, the present invention provides a composition of an 8-arm polyethylene glycol maleimide derivative and a phenolic polymerization inhibitor. The ingredient and content of the polymerization inhibitor in the composition are reasonably chosen, thereby significantly increasing stability of the polyethylene glycol maleimide derivative, effectively avoiding the undesirable effect of gel solidifying due to polymerization during storage and transportation, and extending a pot life and shelf life of a product thereof.

In an embodiment, the present disclosure pertains to a method of changing the glass transition temperature of a polymer. In some embodiments, the polymer includes at least one hydrazone-containing compound. In general, the methods of the present disclosure include one or more of the following steps of: (1) applying light to the polymer; and (2) thereby changing the glass transition temperature of the polymer. In another embodiment, the present disclosure pertains to a polymer having a light-adjustable glass transition temperature. In some embodiments, the polymer includes at least one hydrazone-containing compound.

In an embodiment, the present disclosure pertains to a method of changing the glass transition temperature of a polymer. In some embodiments, the polymer includes at least one hydrazone-containing compound. In general, the methods of the present disclosure include one or more of the following steps of: (1) applying light to the polymer; and (2) thereby changing the glass transition temperature of the polymer. In another embodiment, the present disclosure pertains to a polymer having a light-adjustable glass transition temperature. In some embodiments, the polymer includes at least one hydrazone-containing compound.

To provide a curable fluorinated polymer excellent in solubility in an alcohol, a method for its production and a cured product of the fluorinated polymer. A fluorinated polymer comprising units represented by the following formula (1), wherein in at least some of the units represented by the formula (1), Z.sup.1 is NR.sup.1NR.sup.2H or NR.sup.3OR.sup.4: ##STR00001##
in the formula (1), X.sup.1 and X.sup.2 are each independently a hydrogen atom or a fluorine atom, Q.sup.1 is a single bond or an etheric oxygen atom, R.sup.f1 is a fluoroalkylene group, or a fluoroalkylene group with at least 2 carbon atoms, having an etheric oxygen atom between carbon-carbon atoms, Z.sup.1 is NR.sup.1NR.sup.2H, NR.sup.3OR.sup.4 or OR.sup.5, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a hydrogen atom or an alkyl group, and R.sup.5 is an alkyl group.

To provide a curable fluorinated polymer excellent in solubility in an alcohol, a method for its production and a cured product of the fluorinated polymer. A fluorinated polymer comprising units represented by the following formula (1), wherein in at least some of the units represented by the formula (1), Z.sup.1 is NR.sup.1NR.sup.2H or NR.sup.3OR.sup.4: ##STR00001##
in the formula (1), X.sup.1 and X.sup.2 are each independently a hydrogen atom or a fluorine atom, Q.sup.1 is a single bond or an etheric oxygen atom, R.sup.f1 is a fluoroalkylene group, or a fluoroalkylene group with at least 2 carbon atoms, having an etheric oxygen atom between carbon-carbon atoms, Z.sup.1 is NR.sup.1NR.sup.2H, NR.sup.3OR.sup.4 or OR.sup.5, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a hydrogen atom or an alkyl group, and R.sup.5 is an alkyl group.

In an embodiment, the present disclosure pertains to a method of changing the glass transition temperature of a polymer. In some embodiments, the polymer includes at least one hydrazone-containing compound. In general, the methods of the present disclosure include one or more of the following steps of: (1) applying light to the polymer; and (2) thereby changing the glass transition temperature of the polymer. In another embodiment, the present disclosure pertains to a polymer having a light-adjustable glass transition temperature. In some embodiments, the polymer includes at least one hydrazone-containing compound.

In an embodiment, the present disclosure pertains to a method of changing the glass transition temperature of a polymer. In some embodiments, the polymer includes at least one hydrazone-containing compound. In general, the methods of the present disclosure include one or more of the following steps of: (1) applying light to the polymer; and (2) thereby changing the glass transition temperature of the polymer. In another embodiment, the present disclosure pertains to a polymer having a light-adjustable glass transition temperature. In some embodiments, the polymer includes at least one hydrazone-containing compound.

The present invention aims to provide a modified polyvinyl acetal resin composition that is excellent in storage stability, has high strength and excellent adhesiveness, and is capable of reducing occurrence of warping or peeling when used for bonding different materials. The present invention relates to a modified polyvinyl acetal resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an imine structure, and an epoxy resin.

To provide a curable fluorinated polymer excellent in solubility in an alcohol, a method for its production and a cured product of the fluorinated polymer. A fluorinated polymer comprising units represented by the following formula (1), wherein in at least some of the units represented by the formula (1), Z.sup.1 is NR.sup.1NR.sup.2H or NR.sup.3OR.sup.4:

##STR00001##

in the formula (1), X.sup.1 and X.sup.2 are each independently a hydrogen atom or a fluorine atom, Q.sup.1 is a single bond or an etheric oxygen atom, R.sup.f1 is a fluoroalkylene group, or a fluoroalkylene group with at least 2 carbon atoms, having an etheric oxygen atom between carbon-carbon atoms, Z.sup.1 is NR.sup.1NR.sup.2H, NR.sup.3OR.sup.4 or OR.sup.5, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each independently a hydrogen atom or an alkyl group, and R.sup.5 is an alkyl group.

The present invention provides a polymer which has a small change in relative permittivity before and after exposure to a high-temperature and high-humidity environment, and is capable of forming a film having few wrinkles; a composition; a piezoelectric composite material; a piezoelectric film; and a piezoelectric element. The polymer of an embodiment of the present invention is a polymer including a repeating unit represented by Formula (A) and a repeating unit represented by Formula (B), in which a content of the repeating unit represented by Formula (A) is 60% by mole or more with respect to all repeating units of the polymer, a content of the repeating unit represented by Formula (B) is 1% to 40% by mole with respect to all repeating units of the polymer, and the polymer includes no repeating unit represented by Formula (C), or in a case where the polymer includes the repeating unit represented by Formula (C), a content of the repeating unit represented by Formula (C) is 5% by mole or less with respect to all repeating units of the polymer.

##STR00001##