Extrinsically functional polymers

The lUPAC definition for a functional polymer is a polymer that bears specified chemical groups or polymer that has specified physical, chemical, biological, pharmacological, or other uses which depend on specific chemical groups [3]. The functional polymers are of two basic types intrinsically and extrinsically functional polymer. Intrinsically functional polymers are where the polymers themselves offer a unique range of properties for different applications, while extrinsically functional polymers are those composite materials containing dispersed fine particles of a functional material, such as magnetite (FejO ), carbon black in a conventional polymer. 

Proteins, the polymer of amino acids, are highly specific in structure and the overall structure of a protein is known as conformation. All proteins are conformation dependent for their biological function. Conformation of a protein is generated from the specific sequence of the amino acids during formation of the polymer in association with multiple intrinsic and extrinsic factors. The process of attaining the conformation after polymerization of amino acids in to polypeptide and acquiring the conformation is known as protein folding. 

The poor stability of some semiconducting polymers and their sensitivity to external factors often make it difficult to deduce true intrinsic properties of a certain material [101,102]. Most commonly, the off-currents in a TFT are governed by extrinsic factors and it also has an impact on subthreshold slope, threshold voltages, and bias stress. In fact, this sensitivity prompted some researchers to use OSC materials as gas and chemical sensors in TFT devices [103,104]. The observed selective sensitivity is related either to the chemical nature of the semiconductor functionalities or the interaction of the grain... 

The magnitude of T, also depends on several factors. For example, any intrinsic modification to the composition of the polymer chain as a result of changing the sequence or distribution of the different domains, or extrinsic factors such as salt additions, that modifies the tendency of water molecules to take part in hydrophilic vs. hydrophobic hydration will alter the clathrate structure and modify the T,. This effect is a result of both the mean polarity of the polymer chain and the molecular architecture and distribution of the different amino acid domains in the ELRs [27]. Tt can also be affected by the polymer concentration and by other factors, such as changes in pH or the oxidation state of a side chain or functional group, the... 

The parameters aj and a2 in Equation 5 measure the tendency of the scanning tip to orient the polymer chains and move them towards the center of the scan area. Presumably, a j and a2 are functions of the width of the perturbed region surrounding a scan line, the magnitude of the tip-polymer interaction, and the relaxation time of the polymer s (viscoelastic) response to this perturbation. By changing these parameters one can manipulate the morphology of the scan-induced pattern. One way to modify the viscoelastic response of the polymer is to vary the temperature and fast-scan frequency at which images are acquired. Extrinsic... 

Self-healing or restoration of lost functionalities without external help is a dream come true with self-healing polymers (Ai ssa et a/., 2012). Healing mechanisms can be extrinsic (the healing compound is isolated from the polymer matrix in capsules, fibers or nanocarriers) or intrinsic (the polymer chains temporarily increase mobility and flow to the damaged area) (Billiet et al, 2013) and are responsible for restoration of properties such as structural integrity (White et fll, 2001), surface aesthetics (Yao et a/., 2011), electrical conductivity (Tee et fl/., 2012), hydrophobicity and hydrophilicity (Ionov and Synytska, 2012), mechanical properties (Jones et al, 2013), etc. 

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