Dow Chemical Company

About: Dow Chemical Company is a company organization based out in Mumbai, India. It is known for research contribution in the topics: Polymer & Catalysis. The organization has 17250 authors who have published 23852 publications receiving 450207 citations. The organization is also known as: Dow & Dow Chemical.

A new class of polymers: Starburst-dendritic macromolecules

Abstract: This paper describes the first synthesis of a new class of topological macromolecules which we refer to as “starburst polymers.” The fundamental building blocks to this new polymer class are referred to as “dendrimers.” These dendrimers differ from classical monomers/oligomers by their extraordinary symmetry, high branching and maximized (telechelic) terminal functionality density. The dendrimers possess “reactive end groups” which allow (a) controlled moelcular weight building (monodispersity), (b) controlled branching (topology), and (c) versatility in design and modification of the terminal end groups. Dendrimer synthesis is accomplished by a variety of strategies involving “time sequenced propagation” techniques. The resulting dendrimers grow in a geometrically progressive fashion as shown: Chemically bridging these dendrimers leads to the new class of macromolecules—”starburst polymers” (e.g., (A)n, (B)n, or (C)n).

High-Resolution Inkjet Printing of All-Polymer Transistor Circuits

Abstract: Direct printing of functional electronic materials may provide a new route to low-cost fabrication of integrated circuits. However, to be useful it must allow continuous manufacturing of all circuit components by successive solution deposition and printing steps in the same environment. We demonstrate direct inkjet printing of complete transistor circuits, including via-hole interconnections based on solution-processed polymer conductors, insulators, and self-organizing semiconductors. We show that the use of substrate surface energy patterning to direct the flow of water-based conducting polymer inkjet droplets enables high-resolution definition of practical channel lengths of 5 micrometers. High mobilities of 0.02 square centimeters per volt second and on-off current switching ratios of 10 5 were achieved.

Starburst Dendrimers: Molecular-Level Control of Size, Shape, Surface Chemistry, Topology, and Flexibility from Atoms to Macroscopic Matter

Abstract: Starburst dendrimers are three-dimensional, highly ordered oligomeric and polymeric compounds formed by reiterative reaction sequences starting from smaller molecules—“initiator cores” such as ammonia or pentaerythritol. Protecting group strategies are crucial in these syntheses, which proceed via discrete “Aufbau” stages referred to as generations. Critical molecular design parameters (CMDPs) such as size, shape, and surface chemistry may be controlled by the reactions and synthetic building blocks used. Starburst dendrimers can mimic certain properties of micelles and liposomes and even those of biomolecules and the still more complicated, but highly organized, building blocks of biological systems. Numerous applications of these compounds are conceivable, particularly in mimicking the functions of large biomolecules as drug carriers and immunogens. This new branch of “supramolecular chemistry” should spark new developments in both organic and macromolecular chemistry.