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Polyvinylcarbazole (PVK) is a temperature-resistant [2] thermoplastic polymer produced by radical polymerization from the monomer N-vinylcarbazole. It is a photoconductive polymer and thus the basis for photorefractive polymers and organic light-emitting diodes .
Upon exposure to γ-irradiation, N-vinylcarbazole undergoes solid-state polymerisation. [ 5 ] It is produced by the vinylation of carbazole with acetylene in the presence of base.
According to ASTM D883, stress cracking is defined as "an external or internal crack in a plastic caused by tensile stresses less than its short-term mechanical strength". This type of cracking typically involves brittle cracking, with little or no ductile drawing of the material from its adjacent failure surfaces. [ 1 ]
The copolymer Poly(vinylidene fluoride-co-hexafluoropropylene) or PVDF-HFP is used as a co-polymer in the blades of artificial turf. [17] Addition of organoclay to PVDF-HFP via melt compounding stabilizes the β piezoelectric phase. [18] Copolymers of PVDF are also used in piezoelectric and electrostrictive applications.
PVC is widely and heavily used in construction and building industry, [9] For example, vinyl siding is extensively is a popular low-maintenance material, particularly in Ireland, the United Kingdom, the United States, and Canada.
This is the photoluminescence of two very similarly structured polyfluorene derivatives. The one on the left (purple) is a copolymerization of a fluorene derivative, benzene and oxadiazole molecules and the one on the right (light green) has the structure directly below this image.
Polycarbonate has a glass transition temperature of about 147 °C (297 °F), [8] so it softens gradually above this point and flows above about 155 °C (311 °F). [9] Tools must be held at high temperatures, generally above 80 °C (176 °F) to make strain-free and stress-free products.
Poly (HA MCL) from hydroxy fatty acids with medium chain lengths including six to 14 carbon atoms, can be made for example, by Pseudomonas putida. A few bacteria, including Aeromonas hydrophila and Thiococcus pfennigii , synthesize copolyester from the above two types of hydroxy fatty acids, or at least possess enzymes that are capable of part ...