Block copolymer compositions, prepregs, and laminates made thereform

A circuit subassembly, comprising:

• a conductive metal layer,
• a substrate coated with a resin composition, wherein the resin composition comprises:
• a) 5 to 99 wt. % of a block copolymer, wherein the block copolymer contains at least an A block and at least one of B or B′ or C block;
• wherein each A block is a non hydrogenated poly(acyclic conjugated diene) polymer comprising polymerized units of at least one acyclic conjugated diene;
• each B block is a poly(1,3-cyclodiene) homopolymer with GPC block Mp of <25 kg/mol,
• each B′ block is a poly(1,3-cyclodiene-co-monoalkenyl arene) copolymer with GPC block Mp of <30 kg/mol
• each C block is a poly(alkenyl arene) polymer or copolymer containing at least one high Tg alkenyl arene unit having a Tg of >100° C., and
• the block copolymer has a GPC peak molecular weight Mp of <50 kg/mol before coupling;
• the block copolymer has a GPC peak molecular weight Mp multiplied by the A block content weight fraction of >500 g/mol;
• b) from 0.1 to 10 wt. % of a cure initiator;
• and
• c) up to 95 wt. % of one or more additives selected from a multi-functional co-curable additive, a diene based rubber, a halogenated or non halogenated flame retardant, an inorganic or organic filler or fiber, an antioxidant, a adhesion promotor, and a film forming polymer;
• wherein the circuit subassembly has a dissipation factor (Df) of less than 0.006 at 10 GHz and a dielectric constant Dk of less than 3.8 at 10 GHz.