Bimodal polymer

Bimodal polymer, 20 165 Bimodal polymerization, 20 531 Bimodal reactor technology, for high density polyethylene, 20 170 Bimodal weight ratio, 70 17 Bimolecular reaction, 74 625 Bimolecular recombination coefficient, 74 833... 

TABLE 2. Adhesive Properties of Bimodal Polymers on a Nonpolar Substrate"... 

M Ratzsch, and W. NeiBl, Bimodal Polymers Based on PP and PE (German), in Aufbereiten von Polymeren mit Neuartigen Eigenschaften, VDI Verlag, Diisseldorf 1995, ISBN 318 234 191 X. 

Slurry processes in hydrocarbon diluent are used in the production of HDPE, including bimodal polymers produced in the cascade process in which different hydrogen concentrations are applied in two or more reactors in series. Liquid loop reactors are generally used with a light hydrocarbon diluent such as isobutane, whereas heavier hydrocarbon diluents are typically used in continuous stirred tank reactors. 

Bimodal Polymer from Aluminophosphate-Supported Catalysts... 

Catalyst Is mixed with a propane diluent and fed to the compact prepolymerization reactor. Cocatalyst, ethylene and hydrogen are also fed into this reactor. The pre-polymerized slurry is sent to the loop reactor, which is designed for supercritical conditions and operates at 75-100°C and 55-65 bar. Typically, lower molecular weight and higher density components of the bimodal polymers are produced in the loop reactor. 

Many different loop reactor configurations are used in industrial processes. The loop can be either in a vertical (Phillips and Spheripol processes [72, 73]) or in a horizontal position (USl process). The pipe can also be bent into multiple legs to increase the reaction volume. Several loops can be arranged in series to produce bimodal polymer, as in the case of Spheripol and Borstar processes [74]. Alternatively, the series of loop reactors can be operated as one single unit to increase average residence time and throughput. 

Hagn, C. Wittkop, M. Kreitmeier, S. Trautenberg, H. L. Holzl, T. Goritz, D., The Creation and Spatial Structure of End-Linked Bimodal Polymer Networks A Monte Carlo Study. Polym. Gels Networks 1997,5, 327-337. 

Sotta, P., Local Order in Monomodal and Bimodal Polymer Networks Monte Carlo Simulations. Macromolecules 1998, 31, 8417-8422. 

Subramanian, P. R. Galiatsatos, V, Stress-Optical Properties of Bimodal Polymer Networks. Macromol. Symp. 1993, 76, 233-238. 

ABA Stereoblock Pol3nners From DMA and TrMA. The synthesis of ABA stereoblock pol)nners of PMMA were carried out using the bifunctional initiator (DPE Li ). Table 8 lists several ABA stereoblock pol)nners of PMMA synthesized from various combinations of DMA and TrMA. Because homopolymer analysis indicated a bimodal polymer distribution for bifunctionally initiated MMA, this monomer was not used in the ABA stereoblock pol)nner syntheses. 

PP will continue to develop in niche markets where its advantages over PE and PVC are of importance, as well as in new applications where it is not confronted with existing specifications. TPOs are still in their growing period and their advantages over elastomers are not yet fully exploited. New improved PP are promised by different suppliers, based on catalyst modifications (metallocenes, bimodal polymers, etc.). The flexible PP copolymers are a possible candidate, especially in the telecommunication cables, provided they can be processed on standard PE and PVC equipment. 

Figure 4.42 Effect of particle size ratio on the relative viscosity of stable suspensions of bimodal polymer particles. The data were obtained at a shear stress = 1 dyne/cm and for suspensions with a particle concentration f = 0.65. (From Ref. 69.)...

SHE Shen, W., Smith, G.R., Knobler, C.M., and Scott, R.L., Tricritical phenomena in bimodal polymer solutions. Three-phase coexistence curves for the system polystyrene (1) + polystyrene (2) + methylcyclohexane, J. Phys. Chem., 94, 7943, 1990. 

Subramanian PR, Galiatsatos V. Stress-optical properties of bimodal polymer networks. Macromol Symp 1993 76 233-8. 

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