atactic


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Related to atactic: syndiotactic polymer

atactic

[ā′tak·tik]
(organic chemistry)
Of the configuration for a polymer, having the opposite steric configurations for the carbon atoms of the polymer chain occur in equal frequency and more or less at random.
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References in periodicals archive ?
Mattice, "Molecular Origin of Demixing, Prior to Crystallization, of Atactic Polypropylene/Isotactic Polypropylene Blends upon Cooling from the Melt," J.
In Area 3, cold-crystallization occurs, what means that PLA2003D is not atactic but crystallizes very slowly.
Mulhaupt, "Determination of plateau moduli and entanglement molecular weights of isotactic, syndiotactic and atactic polypropylenes synthesized with metallocene catalysts," Macromolecules 1998.
In the same manner, the angles between the transition dipole moment vectors of an absorbing group and the chain axis were determined in polymers such as PMMA [13], atactic PSt [25], poly(styrene-acrylonitrile) [26], poly(vinyl phenol) [27], and poly(2,6-dimethyl 1,4-phenylene oxide) [28].
Resins made with this catalyst have high purity, very little atactic content, low acidity, and low chloride levels.
From Industrial Polymerisation Wastes to High Valued Material: Interfacial Agents for Polymer Blends and Composites based on Chemically Modified Atactic Polypropylenes 3.
2] catalyst to copolymerize atactic polypropylene (aPP) macromonomer with propylene to produce LCBPP.
The material is modified with a modifier selected from a group including: Atactic PolyPropylene (APP), Amorphous Poly Alpha Oletin (APOA), Thermoplastic PolyOlefin (TPO), Styrene-Butadiene-Styrene (SBS), Styrene-Ethylene-Butadiene-Styrene (SEBS) and synthetic rubber.
Backbone chemical structure Three structural factors affect the value of Tg in atactic polymers.
Neither material contains low-molecular-weight atactic fractions, making them suitable for pharmaceutical and food applications.
IGI refines, blends, compounds, markets and trades paraffin and synthetic waxes, white oils and petrolatum and atactic polypropylenes throughout North America and internationally.
Isotactic PP (i-PP) is able to crystallize because of the polymer chains can be packed efficiently to form a semi-crystalline structure, whereas the random arrangement of methyl groups along the polymer chain leads to formation of atactic, amorphous PP.