PP Systems

Amino-dehydrogenation (SnH) using the LA/PP system was also studied with the 3,6-dinitro-l,8-naphthyridines (87a-87d) (86JHC473 93LA471). Besides mono amino products, diamino products are also obtained the yields are, however, moderate. 

Tliis methodology has also been extended to the use of liquid methylamine/ potassium permanganate (LMA/PP system). When this system is applied to a number of 3-nitro-l,8-naphthyridines (92a-92g), the C-4 position could be successfully substituted by methylamino group yielding 93a-93f. Tire intermediary 4-methylamino-[Pg.305]

Using the same methodology, a number of 3,6-dinitro-l,8-naphthyridines (87a-87g) were converted with the LMA/PP system into the methylamino products (94). Tire methylamino group usually enters at position 4, but in cases where a chloro or methoxy substituent is present at C-2, 2,4-bis(methylamino) derivatives were isolated (97MI3). 

Ha [29] has shown that in PP-HDPE (of high-den-sity PE) dynamically cured EPDM, the cured EPDM act as a compatibilizer to the HDPE-PP system. Blending was done in two ways. EPDM was cured first and then blended with PP and HDPE. In the second case, EPDM was cured in the presence of PP and HDPE using dicu-myl peroxide (DCP) as the vulcanizing agent. In EPDM-rich composition, mechanical properties were increased by increasing the concentration of DCP, whereas in PP-rich composition, the reverse was the case. 

Corsten H, May C (1994) Besonderheiten der Produktion in der Verfahrensindustrie und ihre Auswirkungen auf PPS-Systeme. In Corsten, H. (ed) Handbuch Produktionsmanagement. Gabler, Wiesbaden, pp 871-889... 

Drexl A, Fleischmann B, Gunther H-O, Stadtler H, Tempelmeier H (1994) Konzeptionelle Grundlagen kapazitatsorientierter PPS-Systeme. Zeitschrift fur Betriebswirtschaftliche Forschung 46 1022-1045... 

The preceding observations on the microscopic features of polymer melt devolatilization are not unique to the PS-styrene system, or to strand devolatilization. Similar, though somewhat less rich, features of blister-covered macrobubbles were observed with low-density polyethylene (PE), high-density PE and polypropylene (PP) systems (40,41). Furthermore, Tukachinsky et al. (11) discovered macrobubbles covered with microblisters in a 50-mm-diameter vented SSE, with PS showing more oblong shapes as a result of shearing. The onset of foaming with the application of vacuum was quicker with increased frequency of screw rotation, and the separation was more efficient. 

FIGURE 13.2 Heat release rate (HRR) and total heat release (THR) results at low metal hydroxide loading (2.5%) the PP systems containing nano-MH (prepared by coprecipitation method) is compared to PP and reference system containing micro-MH (heat flux 50kW/m2, samples thickness 4mm). 

FIGURE 13.14 Comparison of the heat release of various intumescent PP systems of 30% total additive content (heat flux 50kW/m2). 

The catalytic role of metal-doped clay surface in fire-induced degradation could be proven and an epoxy-based interlayer has been developed for controlling this activity. As a result of the modification, an increased amount of char residue was formed in fire-retarded PP system. 

As compared to the interphases detected in the case of the Cu/epoxy systems, the interphase measured in the case of the C-fibre/PPS system exhibits a negative stiffness gradient, i.e. decreasing local stiffness of the thermoplastic PPS with increasing distance from the C-fibre surface. The mean width 3/c 107 nm of the stiffness profile is 2.6 times smaller than that of the stiffness profile measured on the Cu/epoxy replica sample. Taking into consideration the spatial constraints imposed on polymer chains due to the presence of the nearby hard wall represented by the surface of the C-fibres, the observed increase in local stiffness can be ascribed to the respective loss in chain flexibility and mobility. 

Enthalpy of ligand substitution in the PtMe2(PP) system (kcal moP )... 

Figure 22 Enthalpy of hgand substitution in the Cp Ru(PP)Cl system and PtMc2(PP) systems, slope = 1.0 R = 0.97)...

Figure 21 Enthalpy of hgand substitution in the CpRu(PP)Cl system and PtMe2(PP) systems slope = 1.1 = 0.96)...

For the PP system, the value of c 6n as a function of 1 is identical for both systems, implying that Eq. (24) applies to the plastic deformation mechanisms at the interface for both systems. 

The results of both studies are summarized in Fig. 26 and it is clear from the data that the PP-blend system has a higher fracture toughness than the pure PP system for all values of X. If one now plots on Fig. 26b the value of oyl7,n- /ac for both systems [using Eq. (24) and the value of <5 obtained from fitting the PP/PA-6 interface data to Eq. (19)],both data sets fall on the same fine as one would expect for two systems which have the same interfacial structure but different values of ocmze. The precise values of the crazing stress in a plastic zone are not directly known for PP and for the blend but the yield stress in tension was meas-... 

The capillary viscosities of HDPE/PP systems at 180 to 210°C were reported (32, 33) to superimpose on the Equation 2 master curve, with ng following the Arrhenius dependence ... 

Figure 28. Reduced frequency relaxation spectrum for LLDPE/PP System 1 (top) and System 2.

Figure 31. Cole-Cole plot, rf vs. n, for LLDPE/PP System 2 at 190 C.

Figure 32. Maxwellian viscosity vs. zero-shear viscosity for LLDPE/PP Systems 1 and 2. Larger symbols indicate homopolymer values.

Stachowiak et al. [138] coupled an automated sample preparation (ASP) system to a chip gel electrophoresis protein profiling (CGE-PP) system to execute an autonomous microfluidic sample preparation and detection of aerosolized bacterial cells and spores on the basis of protein profiling. The combined system, which was field-deployable, was capable of differentiating between bacterial organisms. It operated by collecting... 

A comparison of various properties of the HMO model for linear and mono-cyclic conjugated (pp) systems made it possible to derive numerical values for a set of upper or lower bounds differentiating theoretically between typical aromatic or olefinic behaviour in cyclic tt systems U3f The most important of these are collected in (3). 

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