Polypropylene - Wikipedia
Most commercial polypropylene is isotactic and has an intermediate level of crystallinity between that of low-density polyethylene (LDPE) and high-density polyethylene (HDPE). Isotactic & atactic polypropylene is soluble in p-xylene at 140 °C.
29.5: Correlation of Polymer Properties with Structure
Isotactic polypropene is a hard, clear, strong crystalline polymer that melts at 175o 175 o. It is practically insoluble in all organic solvents at room temperature, but will dissolve to the extent of a few percent in hot 1,1,2,2-tetrachloroethane.
Tacticity - Wikipedia
Polypropylene formed by Ziegler–Natta catalysis is an example isotactic polymer. [8] . Isotactic polymers are usually semicrystalline and often form a helix configuration.
Isotactic polymer | chemistry | Britannica
In major industrial polymers: Polypropylene (PP) Only the isotactic form of polypropylene is marketed in significant quantities. (In isotactic polypropylene, all the methyl [CH 3] groups are arranged along the same side of the polymer chain.) It is produced at low temperatures and pressures using Ziegler-Natta catalysts.
Lamellar orientation in isotactic polypropylene thin films: a ...
2018年10月29日 · While isotactic polypropylene (iPP) is the most commonly used plastic material, crystal structure management has the potential to further expand its applications.
The Processing and Electrical Properties of Isotactic Polypropylene ...
2022年8月18日 · This study investigates the thermal and electrical properties of isotactic polypropylene/copper nanowires (i-PP/CuNWs). The CuNWs were harvested by chemical reduction of CuCl 2 using a reducing agent of glucose, capping agent of hexadecylamine (HDA), and surfactant of PEG-7 glyceryl cocoate.
Thermal expansion of isotactic polypropylene Part I: temperature ...
2023年8月23日 · In this study, the nature of the linear thermal expansion of injection-molded isotactic polypropylene (iPP) was investigated by temperature-variable small-angle X-ray scattering (SAXS) and...
A first principles investigation of isotactic polypropylene
2010年1月1日 · This study focuses primarily on isotactic polypropylene (iPP), which occurs in three different bulk polymorphs depending on how the isotactic chains are packed: monoclinic α, hexagonal β, and triclinic γ.
STRUCTURE AND PROPERTIES OF ISOTACTIC POLYPROPYLENE
The crystal structure of isotactic polypropylene and its chemical-physical properties are described here. The polymer crystallizes in the Cc space group with the following constants of the unit cell: a = 6.65 ± 0.05 Å; b = 20.96 ± 0.15 Å; c = 6.50 ± 0.05 Å β = 99 ° 20 ′ ± 1 °.
Crystallization behavior of isotactic polypropylene containing a ...
2022年1月14日 · Isotactic polypropylene (PP) is one of the most important crystalline polymers. It has good comprehensive properties, such as stiffness, outstanding resistance to stress cracking, marked heat...