The linear rheological responses of wedge‐type polymers

The linear rheological responses of a series of specially designed wedge‐type polymers synthesized by the polymerization of large molecular weight monomers have been measured. These wedge polymers contained large side groups which contained three flexible branch chains per polymer chain unit. The master curves for these polymers were obtained by time temperature superposition of dynamic data at different temperatures from the terminal flow regime to well below the glass transition temperature, T_g. While these polymers maintained a behavior similar to that of linear polymers, the influence of the large side group structure lead to low entanglement densities and extremely low rubbery plateau modulus values, being near to 13 kPa. The viscosity molecular weight dependence was also somewhat higher than that normally observed for linear polymers, tending toward a power law near to 4.2 rather than the typical 3.4 found in entangled linear chains. The glassy modulus of these branched polymers is also found to be extremely low, being less than 100 MPa at T_g ?60 °C. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 899–906     

Janus Graft Block Copolymers: Design of a Polymer Architecture for Independently Tuned Nanostructures and Polymer Properties

The graft‐through synthesis of Janus graft block copolymers (GBCPs) from branched macromonomers composed of various combinations of homopolymers is presented. Self‐assembly of GBCPs resulted in ordered nanostructures with ultra‐small domain sizes down to 2.8 nm (half‐pitch). The grafted architecture introduces an additional parameter, the backbone length, which enables control over the thermomechanical properties and processability of the GBCPs independently of their self‐assembled nanostructures. The simple synthetic route to GBCPs and the possibility of using a variety of polymer combinations contribute to the universality of this technique.     

Copolymerizations of tetraethyl vinylidene phosphonate. Bisphosphonate units in the main polymer chain. II

This is the second part of the article with a subtitle “… The First Synthesis” published by us previously. For this, second part, we have chosen copolymers with low proportion of (‐b‐) units, as well as random copolymers with substantial proportions of (‐b‐) units. This is in contrast to the part I, in which we mostly described alternating copolymerization. In this article, radical copolymerization of tetraethyl vinylidene phosphonate (B) with several vinyl/ethylenic monomers (M₂), namely acrylamide, methacrylamide, methyl methacrylate, n‐butyl acrylate, n‐butyl methacrylate, and styrene has been described and reactivity ratios of monomers as well as the average length of the comonomer blocks (n) have been determined (r₁ = 0). It has been found, that (as it should be) there is a proportionality between r₂ (=k_m2M2/k_m2B) and n. Moreover, there is a proportionality between r₂ (or n) and the comonomer (M₂) “reactivity,” defined as the rate constant of M₂ addition to the styrene radical. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1614–1621     

Additivity of integrals on generalized measure spaces

It is proved that the integral is additive on simple summable functions of a generalized measure space.     

Monomeric cis-isothiocyanato complexes. Crystal and molecular structure of [Mn(mep)2(NCS)2] (mep=4-methoxy-2-(5-methoxy- 3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine)

The crystal and molecular structures of [Mn(mep)2- (NCS)2] ({ {mep}}=4-methoxy-2-(5-methoxy-3-methyl-1H-pyrazol-1-yl)-6-methylpyrimidine) have been determined by X-ray crystallography. The crystal structure of the title compound is built up of isolated [Mn(mep)2(NCS)2] molecules with the stereochemistry of a distorted octahedron for the MnN6 chromophore. The e.p.r. (Q-band) data are in agreement with the structural data.