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Branch point in a polymer. Polymer architecture in polymer science relates to the way branching leads to a deviation from a strictly linear polymer chain. [1] Branching may occur randomly or reactions may be designed so that specific architectures are targeted. [1] It is an important microstructural feature.
In polymer chemistry, branching is the regular or irregular attachment of side chains to a polymer's backbone chain. It occurs by the replacement of a substituent (e.g. a hydrogen atom ) on a monomer subunit by another covalently-bonded chain of that polymer; or, in the case of a graft copolymer , by a chain of another type.
Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer. A polymer which contains only a single type of repeat unit is known as a homopolymer, while a polymer containing two or more types of repeat units is known as a copolymer. [22] A terpolymer is a copolymer which contains three types of repeat units ...
Crystal structure of a first-generation polyphenylene dendrimer reported by Müllen et al [5] A first-generation "cyanostar" dendrimer and its STM image [6]. The first dendrimers were made by divergent synthesis approaches by Fritz Vögtle in 1978, [7] R.G. Denkewalter at Allied Corporation in 1981, [8] [9] Donald Tomalia at Dow Chemical in 1983 [10] and in 1985, [11] [12] and by George R ...
A monomer with functionality of 3 or more will introduce branching in a polymer and will ultimately form a cross-linked macrostructure or network even at low fractional conversion. The point at which a tree-like topology transits to a network is known as the gel point because it is signalled by an abrupt change in viscosity .
Image credits: Green____cat Cyber and media psychologist Mayra Ruiz-McPherson, PhD(c), MA, MFA, explains that broadly speaking, "negative news" can describe two kinds of events and happenings ...
Polymer chemistry is a sub-discipline of chemistry that focuses on the structures, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are also applicable through a wide range of other chemistry sub-disciplines like organic chemistry , analytical ...
An elderly straphanger was randomly shoved onto subway tracks at the Herald Square station in Manhattan on Sunday afternoon, according to police.