Polymer

A polymer comprising structural units (A) derived from ethylene and constitutional units (B) represented by formula (1) below and optionally comprising at least one type of constitutional units (C) selected from the group consisting of constitutional units represented by formula (2) below and constitutional units represented by formula (3) below,

• wherein where the total number of the units (A), the units (B), and the units (C) is 100%, the number of the units (A) accounts for 70% to 99% and the total number of the units (B) and the units (C) accounts for 1% to 30%;
• and where the total number of the units (B) and the units (C) is 100%, the number of the units (B) accounts for 1% to 100% and the number of the units (C) accounts for 0% to 99%,
• in formula (1) R represents a hydrogen atom or methyl group,
• L1 represents —CO—O—, —O—CO—, or —O—,
• L2 represents a single bond, —CH2—, —CH2—CH2—, —CH2—CH2—CH2—, —CH2—CH(OH)—CH2—, or —CH2—CH(CH2OH)—,
• L3 represents a single bond, —CO—O—, —O—CO—, —O—, —CO—NH—, —NH—CO—, —CO—NH—CO—, —NH—CO—NH—, —NH—, or —N(CH3)—,
• L6 represents an alkyl group having 14 to 30 carbon atoms;
• in formula (2),
• R represents a hydrogen atom or a methyl group,
• L1 represents —CO—O—, —O—CO—, or —O—,
• L4 represents an alkylene group having 1 to 8 carbon atoms,
• L5 represents a hydrogen atom, an epoxy group, —CH(OH)—CH2OH, a carboxyl group, a hydroxyl group, an amino group, or an alkylamino group having 1 to carbon atoms;
• in each of the horizontal chemical formulae represented by L1, L2, or L3 in formula (1) and formula (2) above, the left side thereof corresponds to the top side of formula (1) or formula (2) and the right side thereof corresponds to the bottom side of formula (1) or formula (2),
• wherein a ratio A defined by formula (I) is 0.95 or less, and
• wherein A=α1/α0 (I) in formula (I),
• wherein α1 is a value obtained by a method comprising:
• measuring the absolute molecular weight and the intrinsic viscosity of a polymer by gel permeation chromatography using an apparatus equipped with a light scattering detector and a viscosity detector, plotting the measured data with logarithms of absolute molecular weights as abscissa against logarithms of intrinsic viscosities as ordinate, approximating with formula (I-I) in the least squares sense logarithms of absolute molecular weights and logarithms of intrinsic viscosities within the range of from the logarithm of the weight-average molecular weight of the polymer to the logarithm of the z-average molecular weight of the polymer on the abscissa, and representing the slope of the straight line showing formula (I-I) by α1,
• log [η1]=α1 log M1+log K1 formula (I-I)
• in formula (I-I), [η1] represents the intrinsic viscosity (unit:
• dl/g) of the polymer, M1 represents the absolute molecular weight of the polymer, and K1 is a constant;
• and
• wherein in formula (I), α0 is a value obtained by a method comprising:
• measuring the absolute molecular weight and the intrinsic viscosity of a polyethylene standard substance 1475a by gel permeation chromatography using an apparatus equipped with a light scattering detector and a viscosity detector, plotting the measured data with logarithms of absolute molecular weights as abscissa against logarithms of intrinsic viscosities as ordinate, approximating with formula (I-II) in the least squares sense logarithms of absolute molecular weights and logarithms of intrinsic viscosities within the range of from the logarithm of the weight-average molecular weight of the polyethylene standard substance 1475a to the logarithm of the z-average molecular weight of the polymer on the abscissa, and representing the slope of the straight line showing formula (I-II) by α0,
• log [η0]=α0 log M0+log K0 formula (I-II)
• in formula (I-II), [η0] represents the intrinsic viscosity (unit:
• dl/g) of the polyethylene standard substance 1475a, M0 represents the absolute molecular weight of the polyethylene standard substance 1475a, and K0 is a constant;
• and
• wherein in the measurement of the absolute molecular weight and the intrinsic viscosity of the polymer and the polyethylene standard substance 1475a by gel permeation chromatography, the mobile phase is orthodichlorobenzene and the measurement temperature is 155° C.