In this article, the annealing effect on the physical properties of isotactic
polypropylene (iPP) fibers is studied using automated VAWI interference microscope.
Gen 4 is an offshoot of Gen 3 introduced in 1990, using diesters like diisobutyl phthalate as internal donors and silanes like dicyclopentyl-dimethoxy silane (DCPDMS) as external donors for super high activity and high selectivity for isotactic
polypropylenes of different molecular characteristics: influence of crystallization conditions and annealing on the fracture behaviour," Journal of Materials Science, vol.
The madar fiber, a close relative of jute and hemp, was used as reinforcing filler for isotactic
polypropylene for the first time, mainly due to the cost-effectiveness and natural abundance.
Treofan is developing these ultrathin capacitor films with a high level of thickness homogeneity, electrical field stressability, low energy losses and very good mechanical characteristics using Borealis' Borclean super pure, high isotactic
polypropylene homopolymer with a novel polymer design.
The most poignant example for how structural configuration of these materials affected the LCST is poly(N-isopropyl acrylamide) (PNIPAM): a gradual decrease is recorded with increasing the isotacticity, and, for an isotactic
(mm) triad, the insolubility in water appears to be over 72%, although the atactic (mr) PNIPAM is one of the representative water-soluble polymers .
Unique chain-shuttling technology is used to make Dow Performance Plastics' INTUNE Olefin Block Copolymers (OBCs), which mix segments of crystalline isotactic
polypropylene (PP) and crystalline polyethylene (PE) to make a polymer compatible with both.
Among the topics are the development of a hydrophobic microporous isotactic
polypropylene membrane for a membrane contactor application, tensile properties and the degradability of a polyvinyl alcohol and starch succinate blend, flooding with biopolymer from microbes derived from mushrooms and cabbage to enhance the sweep efficiency in enhanced oil recovery, synthesizing hydroxyapatite with the sol-gel dip-coating method on a ceramic support, and potential technologies for decoloring batik wastewater.
Typical Glass-Transition Values Polymer Tg, C Nylon 6 47 Nylon 66 70 PE -80 Polyvinylidene fluoride -35 PP (atactic) -20 Polyvinyl fluoride -20 PP (isotactic
) 0 Poly-3-hydroxybutyrate 15 Polyvinyl acetate 30 Polychlorotrifluoroethylene 45 Polylactic acid 60-65 PET 70 PVC 80 Polyvinyl alcohol 85 PS 95 Polymethyl methacrylate 105 ABS 105 Polytetrafluoroethylene 115 PC 145 Polvsulfone 185 Source: Wikipedia
In the 1950s, the historical achievements, which were subsequently awarded with the Nobel Prize, were reported concerning the helical structures of three different types of polymers, protein in 1951, (1) DNA in 1953 (2) and isotactic
polypropylene in 1955.