An optical film, wherein a photoelastic coefficient thereof is 1.510.sup.13 (dyn/cm.sup.2).sup.1 or less, an in-plane retardation Re(560) thereof at a wavelength of 560 nm is 1.0 nm or less, an absolute value of a thickness-direction retardation Rth(560) thereof at a wavelength of 560 nm |Rth(560)| is 1.0 nm or less, a change of a ratio Re(560)/d that is a ratio of the in-plane retardation Re(560) at a wavelength of 560 nm relative to a thickness d, the change being a result of storage at a temperature of 60 C. and a humidity of 90% for 4 hours, is 0.510.sup.5 or less, and a change of a ratio Rth(560)/d that is a ratio of the thickness-direction retardation Rth(560) at a wavelength of 560 nm relative to the thickness d, the change being a result of storage at a temperature of 60 C. and a humidity of 90% for 4 hours, is 0.510.sup.5 or less.

The present invention provides a thermoplastic elastomer composition for foaming. The thermoplastic elastomer composition comprises: (A) an ethylene-based copolymer; (B) an olefin block copolymer; (C) an unsaturated aliphatic rubber; and (D) a crosslinking agent. The olefin block copolymer is different from the ethylene-based copolymer. The weight ratio of the unsaturated aliphatic rubber (C) to the olefin block copolymer (B) is 1:1.5 to 1:5.

A phase difference film composed of a resin C containing a copolymer P including a polymerization unit A and a polymerization unit B, the phase difference film including a lamellar phase separation structure that generates a structural birefringence, the phase separation structure including a phase (A) having the polymerization unit A as a main component and a phase (B) having the polymerization unit B as a main component, and the phase difference film satisfying the formulae (1A): f(A)>0.5 and (2):D(A)>D(B), or the formulae (1B): f(B)>0.5 and (2). f(A) represents a total weight ratio of the polymerization unit A in the copolymer P, f(B) represents a total weight ratio of the polymerization unit B in the copolymer P, D(A)=ReA(450)/ReA(550), D(B)=ReB(450)/ReB(550), and ReA(450), ReA(550), ReB(450) and ReB(550) are as defined in the description.

The present disclosure is directed to triblock copolymer based anion exchange membranes (AEMs) and methods for making same. The membranes are useful as separators in electrochemical devices, such as fuel cells, electrolyzers, and redox flow batteries.

A resin composition contains a maleimide compound (A), a cyanate ester compound (B), a polyphenylene ether compound (C) with a number average molecular weight of not lower than 1000 and not higher than 7000 and represented by Formula (1), and a block copolymer (D) having a styrene backbone. In Formula (1), X represents an aryl group; (YO)n.sub.2- represents a polyphenylene ether moiety; R.sub.1, R.sub.2, and R.sub.3 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group; n.sub.2 represents an integer of from 1 to 100; n.sub.1 represents an integer of from 1 to 6; and n.sub.3 represents an integer of from 1 to 4.

##STR00001##

Branched block copolymers, derived from alkenyl aromatic hydrocarbon-1,3-diene monomer system, and branched polyisoprene homopolymers, derived from isoprene, are obtained by polymerization in the presence of an anionic initiator; at a temperature from 0 C. to 100 C.; followed by coupling with a multifunctional coupling agent of formula (R.sup.1O).sub.3SiYSi(OR.sup.2).sub.3, wherein R.sub.1 and R.sub.2 are independently C.sub.1-C.sub.6 alkyl groups; and Y is a C.sub.2-C.sub.8 alkylene group. The polymers thus obtained can be used in many applications, including rubber cements having high solids content and low zero shear viscosities, and for producing aqueous latices therefrom.

A phase difference film composed of a resin containing a copolymer including polymerization units A and B, the phase difference film including a cylindrical phase separation structure that generates a structural birefringence, the phase separation structure including a phase (A) having the polymerization unit A as a main component and a phase (B) having the polymerization unit B as a main component, and the phase difference film satisfying the following condition (1) or (2). Condition (1): D(A)>D(B) and f(B)>0.5, and a direction giving a maximum refractive index among in-plane directions and an orientation direction of a cylinder in the phase separation structure are parallel to each other. Condition (2): D(A)>D(B) and f(A)>0.5, and a direction giving a maximum refractive index among in-plane directions and an orientation direction of a cylinder in the phase separation structure are orthogonal to each other.

A resin composition including a hydrogenated block copolymer product [D] and a plasticizer, wherein: the hydrogenated product [D] is a hydrogenated product obtained by hydrogenating a block copolymer [C] composed of a polymer block [A] containing a repeating unit [I] derived from an aromatic vinyl compound as a main component, and a polymer block [B] containing the repeating unit [I] derived from an aromatic vinyl compound and a repeating unit [II] derived from a chain conjugated diene compound as main components; a ratio of the block [A] and the block [B], and a ratio of the unit [I] and the unit [II] are in specific ranges, and, in the hydrogenated product [D], 90% or more of all unsaturated bonds in the block copolymer [C] are hydrogenated.

A foamed article formed by foam injection molding or foam extrusion of a composition is disclosed. The article is formed from a molding composition consisting essentially of: 100 phr of at least two different hydrogenated styrenic block copolymers (HSBC), a first HSBC and a second HSBC, having different molecular weights, a molecular weight ratio of at least 1.2:1, respectively; and a weight ratio of ranging from 5:95 to 95:5, respectively; 10-55 phr of a polypropylene having a melt flow of at least 2 g10/min; and optionally up to 55 phr of a plasticizer, selected from hydrocarbon based oils, fatty acids, triglyceride oils, and mixtures thereof. The composition has a melt flow rate of 2-50 g/10 min, a Shore A hardness of 60-90, a melt strength (F) of at least 0.010 N, and a melt strength (V) of at least 10.

A method of treating a wearable device to resist sebum, the method including providing a body having an elastic material having a polymeric backbone where a portion of the polymeric backbone is unsaturated and the body has an outer surface. The method further includes forming a crosslinked matrix within an outer layer of the body surrounding an inner layer of the body such that the outer layer has less affinity to sebum than the inner layer of the body.