Polymers with intrinsic properties

Apart from the tunable color emission covering the full visible range, there are several other aspects supporting the interest in PTs for PLEDs. PTs are examples of classical conjugated polymers with intrinsic one-dimensionality of the polymer chain. Alignment can induce anisotropy in macroscopic properties such as electron transport or optical properties. Polarized... 

Another approach to CPL is the synthesis of conjugated polymers with intrinsic chiro-optical properties. A variety of polymers with CPPL have been synthesized so far. Most of them are based upon well-known conjugated polymers such as poly(thiophene)s [4,111], polyphenylene vinylene)s [123], poly(thienylene vinylene)s [124], ladder polymers [125], PPPs [126], polyphenylene ethynylene)s, [127] and poly(fluorenes) [128]. All of them have been modified with chiral side-chains, which induce the chiro-optical properties. 

Conjugated polymer with intrinsic electrocatalytic properties... 

Polymers with intrinsic microporosily, also abbreviated as PIMs, are soluble porous polymers formed from non-reversible condensation methods. These polymers cannot pack efflcientiy in the solid state due to rigid ladder-like components. Tliese polymers have a site of contortion in their stmcture and are known for their properties, including gas permeation and selective separation. 

The book was initially eonstrueted with a historical development sequenee of porous polymers eombined with illustrations of structure-property correlations. Eaeh ehapter provides an example of a particular element of porous polymers. Chapter 1 provides a summary of porous polymers and discusses the relationship between structure and function. In Chapter 2, the design principles of porous polymers are diseussed and modification methods are introdueed, while Chapter 3 introduees the synthetic routes and reactions used in polymerization. An understanding of these reactions is essential if we are to understand the origin of the ordered or amorphous structure of porous polymers. Chapter 4 describes the first porous polymers, developed in the 1990s and named hypercrosslinked polymers or Davankov-type resins. Chapter 5 focuses on the first soluble polymer with intrinsic microporosity that was reported in 2002. Meanwhile, Chapter 6... 

Table 4.9 Physical properties and permeation properties of polymers with intrinsic microporosity (PIMs)...

Grafting reactions alter the physical and mechanical properties of the polymer used as a substrate. Grafting differs from normal chemical modification (e.g., functionalization of polymers) in the possibility of tailoring material properties to a specific end use. For example, cellulose derivatization improves various properties of the original cellulose, but these derivatives cannot compete with many of the petrochemically derived synthetic polymers. Thus, in order to provide a better market position for cellulose derivatives, there is little doubt that further chemical modification is required. Accordingly, grafting of vinyl monomers onto cellulose or cellulose derivatives may improve the intrinsic properties of these polymers. 

The electronic properties of germanium have led to an interest in incorporating the element into extended polymeric chains due to the intrinsic properties of the polymers themselves or in their use as precursors for material synth-esis. Catalytic co-polymerization of the germylene Ge[N(SiMe3)2]2 with various substituted acetylenes leads to... 

Size exclusion chromatography (SEC) polymer elution profiles yield information regarding the molecular size distributions of polydisperse macromolecules. Polymer molecular weight distribution (MWD) represents an intrinsic property which provides direct correlation with many end-use physical properties and a universal criterion for polymer characterization (1). In order to convert elution profiles or chromatograms into MWD information proper calibration methods are required. SEC molecular weight calibration techniques represent experimental approaches for transformation of polymer elution profiles into MWD information and are dependent upon instrumentation, columns, and the polymer/solvent system under study. 

An AB monomer, 2-(4-hydroxyphenyl)-3-phenyl-6-fluoroquinoxaline [17], was prepared from the reaction of 4-hydroxybenzil and l,2-diamino-4-fluorobenzene and subsequently polymerized under aromatic nucleophilic displacement conditions in NMP. The resultant polymer exhibited an intrinsic viscosity of 1.23 dL/g, a Tg of 247 °C and thin film tensile strength and modulus at room temperature of 107 Mpa and 3.2 GPa, respectively [17]. The same AB monomer was also copolymerized with hydroquinone and 4,4 -difluorodiphenyl sulfone to yield a series of copolymers with interesting properties [17]. The same AB monomer was prepared and polymerized by other researchers to yield a polymer with an intrinsic viscosity of 0.65 dL/g and a Tg of 255 °C [18]. 

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