The differences in sub‐national institutions within large and complex emerging economies have been increasingly noted. Drawing on social network theory and the institution‐based view, we argue that two network structural attributes of domestic firms – centrality and structural holes – have distinctive values in different sub‐national regions where institutional contexts differ widely. In addition, these sub‐national institutional contingencies influence the attractiveness of different network attributes to foreign entrants seeking international joint venture (IJV) partners. Specifically, in regions where the degree of marketization is high, centrally positioned domestic firms are more likely to be selected by foreign entrants as IJV partners. In regions where the degree of marketization is low, domestic broker firms are more attractive IJV partners. Results from the electrical and information technology industries in 18 provinces in China largely support our hypotheses.

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This study explores the relationship between eight distinct brokerage roles of middle managers and their involvement in achieving different strategic goals. The authors argue that each role contributes to different aspects of middle managers’ strategic goals and that some roles are more likely to realize brokerage advantages than others. They further suggest that bridging structural holes may not be an optimal strategy in all situations. Important implications of their model are discussed and several future research directions are proposed.

Thermoplastic elastomers (TPEs) are designed by embedding discrete glassy or semicrystalline domains in an elastomeric matrix. Typical styrenic-based amorphous TPEs are made of linear ABA-type triblock copolymers, where the volume fraction f of the glassy domains A is typically less than 0.3. This limitation ultimately restricts the range of mechanical strength attainable with these materials. We had previously predicted using self-consistent field theory (SCFT) that A(BA′) n miktoarm block copolymers with an approximately 8:1 ratio of the A to A′ block molecular weights and n ≥ 3 should exhibit discrete A domains at considerably larger f and offer potential for the combination of high modulus, high recoverable elasticity, and high strength and toughness. Using transmission electron microscopy and small-angle X-ray scattering on model polystyrene-bpolyisoprene (PS−PI) miktoarm copolymers, we show that such polymers indeed possess discrete PS domains for f values considerably higher than 0.3. The hexagonal morphology with PS cylinders was achieved for f = 0.5 and n = 3. Mechanical testing indicates that these miktoarm materials are strong, tough, and elastic and thus may be potential candidates for a new generation of thermoplastic elastomers.

We report herein the modular synthesis and nanolithographic potential of poly­(dimethylsiloxane-block-methyl methacrylate) (PDMS-b-PMMA) with self-assembled domains approaching sub-10 nm periods. A straightforward and modular coupling strategy, optimized for low molecular weight diblocks and using copper-catalyzed azide–alkyne “click” cycloaddition, was employed to obtain a library of PDMS-b-PMMA and poly­(dimethylsiloxane-block-styrene) (PDMS-b-PS) diblock copolymers. Flory–Huggins interaction parameters, determined from small-angle X-ray scattering experiments, were high for PDMS-b-PMMA (χ ∼ 0.2 at 150 °C), suggesting this diblock copolymer system has promise for sub-10 nm lithographic applications when compared to the corresponding PDMS-b-PS diblock copolymers (χ ∼ 0.1 at 150 °C). Performance evaluation in thin film self-assembly experiments allowed domain periods as small as 12.1 nm to be obtained, which is among the smallest highly ordered nanoscale patterns reported hitherto for thermally annealed materials.

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