Thermoplastic elastomer compositions comprising acrylic multigraft copolymers are described. The multigraft copolymers comprise a rubbery polyacrylate backbone and a plurality of randomly spaced glassy polyacrylate side chains. The multigraft copolymers can be prepared using a facile grafting through method that can provide copolymers with enhanced purity. The acrylic multigraft copolymers exhibit microphase separated morphologies and “superelastomeric” properties, including an elongation at break, stress at break, and/or strain recovery behavior that exceeds that of conventional triblock copolymer polyacrylate thermoplastic elastomers.

A method for preparing a biomass-based conductive hydrogel by 3D printing is provided. Firstly, a cellulose-based macromonomer, a rosin-based monomer, an acrylic acid monomer and an initiator are mixed in a certain proportion, stirred, and dissolved at 25-70° C. Then, diisocyanate in an amount of 5-10 wt % of a total mass of the monomers is added to the mixed solution and mixed uniformly to prepare a 3D printing photosensitive resin solution. An SLA light-curing 3D printer is used to print a hydrogel precursor 1 with a complex shape. Next, the hydrogel precursor 1 is heated to obtain a hydrogel precursor 2 with a dual-curing network. Finally, the obtained hydrogel precursor 2 is swelled in a 1-15 wt % alkaline solution at 5-60° C. for 0.1-10 hours to obtain the biomass-based conductive hydrogel.

A method for preparing a biomass-based conductive hydrogel by 3D printing is provided. Firstly, a cellulose-based macromonomer, a rosin-based monomer, an acrylic acid monomer and an initiator are mixed in a certain proportion, stirred, and dissolved at 25-70° C. Then, diisocyanate in an amount of 5-10 wt % of a total mass of the monomers is added to the mixed solution and mixed uniformly to prepare a 3D printing photosensitive resin solution. An SLA light-curing 3D printer is used to print a hydrogel precursor 1 with a complex shape. Next, the hydrogel precursor 1 is heated to obtain a hydrogel precursor 2 with a dual-curing network. Finally, the obtained hydrogel precursor 2 is swelled in a 1-15 wt % alkaline solution at 5-60° C. for 0.1-10 hours to obtain the biomass-based conductive hydrogel.

A (meth)acrylic copolymer (A) having a mass average molecular weight of 50,000 to 1,000,000, in which the (meth)acrylic copolymer (A) is obtained by polymerizing a monomer mixture including a macromonomer (a) that has a number average molecular weight of 500 or more and less than 6000 and a vinyl monomer (b), and preferably includes 7 to 40% by mass of a repeat unit derived from the macromonomer (a), has sufficient coating workability, adhesive holding power and adhesive property as an adhesive composition.

The present invention describes novel macromonomers containing polyisobutene groups and homo- or copolymers thereof.

Although it has been difficult to stabilize a viscosity and a thixo ratio in a composition containing a (meth)acrylate compound having a polyisobutylene skeleton, the present invention can stabilize the viscosity and the thixo ratio in a photocurable composition containing a (meth)acrylate compound having a polyisobutylene skeleton.

A photocurable composition including a component (A) and a component (B) such that the component (B) is contained in an amount of 0.1 to 15 parts by mass relative to 100 parts by mass of the component (A):

component (A): a (meth)acrylate compound having a polyisobutylene skeleton; and

component (B): a (meth)acrylamide compound.

The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100° C. of 1.00 to 2.50 mm.sup.2/s; and an ester oil (B2) having a kinematic viscosity at 100° C. of 2.51 to 5.00 mm.sup.2/s:

##STR00001##

wherein R.sup.1 is a hydrogen atom or a methyl group; —X.sup.1— is a group represented by —O—, —O(AO).sub.m-, or —NH—, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; R.sup.2 is a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.

The present invention provides a modified block copolymer composition comprising a modified block copolymer containing at least one aromatic vinyl polymer block and at least one conjugated diene polymer block, and having at least one modified terminal modified with a compound having a silicon atom and an acrylic group and/or a methacrylic group.

The present invention aims to provide a curable resin composition excellent in surface curability and deep curability by irradiation with active energy rays such as ultraviolet rays while maintaining sealability. The present invention provides a curable resin composition including the following ingredients (A) to (D): ingredient (A): a polymer which has one or more (meth)acryloyl groups and has a polyisobutylene backbone containing a —[CH2C(CH3)2]- unit, ingredient (B): a radical polymerization initiator, ingredient (C): a triarylphosphine or a triarylphosphine derivative, and ingredient (D): xanthone or a xanthone derivative.

The present invention aims to provide a curable resin composition excellent in surface curability and deep curability by irradiation with active energy rays such as ultraviolet rays while maintaining sealability. The present invention provides a curable resin composition including the following ingredients (A) to (D): ingredient (A): a polymer which has one or more (meth)acryloyl groups and has a polyisobutylene backbone containing a —[CH2C(CH3)2]- unit, ingredient (B): a radical polymerization initiator, ingredient (C): a triarylphosphine or a triarylphosphine derivative, and ingredient (D): xanthone or a xanthone derivative.