PP/HDPE

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. 

Table 9.8 shows the results of MALDI-ToFMS experiments of the selected additives in PP, HDPE, PA6 and PMMA. The observed detection limits are in the technical range of interest. Identification of the additives... 

In some cases, it may be possible to select a polymer as the media material which is similar or identical to one of the components in the mixture to be separated. For example, if the objective is to recover PA and PC from the other components in a mixture, PA media should be added in quantities sufficient to enable PC to report to the negative electrode, the PA would fall to the center since it would be neutral, and the PVC, poly(ethylene terephthalate) (PET), PP, HDPE, HIPS and ABS would report to the positive electrode. The remaining components could sequentially be separated by using HIPS, PP, and PVC media. An eight component mixture would be separated using only four separators (47). 

Sahagun CZ, Gonzalez-Nunez R, Rodrigue D (2006) Morphology of extruded PP/HDPE foam blends. J Cell Plast 42 469 185... 

Diblock copolymers, especially those containing a block chemically identical to one of the blend components, are more effective than triblocks or graft copolymers. Thermodynamic calculations indicate that efficient compat-ibilisation can be achieved with multiblock copolymers [47], potentially for heterogeneous mixed blends. Miscibility of particular segments of the copolymer in one of the phases of the bend is required. Compatibilisers for blends consisting of mixtures of polyolefins are of major interest for recyclates. Random poly(ethylene-co-propylene) is an effective compatibiliser for LDPE-PP, HDPE-PP or LLDPE-PP blends. The impact performance of PE-PP was improved by the addition of very low density PE or elastomeric poly(styrene-block-(ethylene-co-butylene-l)-block styrene) triblock copolymers (SEBS) [52]. 

Fourier Transform Raman Spectroscopy for Prediction of PP Content in PP/HDPE Blends... 

Similar to (TMS -f O2) plasma-treated PP, many of the (TMS -f O2) plasma-treated polymers showed that the three-phase contact line hardly recedes on the wet surface. Specifically, (TMS + O2) plasma-treated PTFE, UHMWPE, PP, HDPE, PVDF, and nylon showed hardly any change in contact area during the receding process. This is due to the strong specific attractive forces formed at the surface underneath the bulk droplet, i.e., the interfacial tension (underneath the droplet) changed due to the interaction of water with the surface. 

Talc is always an attractive subject of such studies due to its platelet structure. In thermoforming and compression molding processes of three resins (PP, HDPE, and PPS), each containing 20% talc, the talc particles were always parallel to the specimen surface, regardless of the resin used. Crystallites grew in a direction normal to the surface of talc particles and thus were perpendicular to the specimen surface. But in the case of unfilled HDPE, crystallites grew parallel to the specimen surface. There was no difference in crystallite growth direction in the case of polypropylene with and without talc. 

Blends of three PP and two HDPE resins having different values of Hq were studied in a capillary viscometer ( 35). Independently of the viscosity ratio, X, at 200 C all blends showed small negative deviation from the log-addltlvlty rule, NDB. The non-equilibrium extrudate swell at low stress (measured after quenching) showed small positive deviation from the additivity rule while at higher stresses the additivity. The NDB tendency for the viscosity combined with the constant critical shear stress for melt fracture, oxp " 2MPa, indicate a better extrudablllty of the PP/HDPE blends than that of the neat resins. 

In newer materials, such as polythene, plasticised PVC and EPE, it is possible to combine the wad/facing as one material, utilising the combined properties of resilience and resistance. Taking this one stage further, wadless caps can now be made from various plastics LDPE, PP, HDPE, etc. In addition there are rubber compounds as discs, bungs or stoppers, i.e. ... 

Stabilization of PP, HDPE, LDPE and LDPE/L-LDPE blends is the main application field of HAS [12]. The polymer matrix influences, to some extent, the efficiency. For example, the light stabilizing effect in LDPE/L-LDPE increased with the relative content of L-LDPE [140]. Differences in the rate of the oxygen uptake were found between 28, R = H doped PP and PE oxidized at 90 °C or irradiated with light having A >290 nm [141]. 

An important observation was published recently on solubility of the nitroxides in PO. Measurements in PP, HDPE, LDPE and L-LDPE revealed [183] that the nitroxides are always less soluble than the respective parent HAS and their diffusion coefficient is lower. Differences up to two orders of magnitude have been observed between PP and LDPE, the solubility being better in PE. The data show that NO are less compatible with PO than the respective NH or NCH3. 

Carstab . [Morton huT.] Benzophe-nones and thiodipropionates uv light stabilizer, antioxidant for PP, HDPE, LDPE, EVA, PVC, PC, acetals, epoxies, some cellulosics, in cosmetics, protective coatings, food use. 

PP/HDPE= 1 1 processability, weld-line strength. Moorwessel a/., 1974... 

PA with carboxylated EPDM and PE PA blended with a mixture of PP, HDPE and EPR... 

Nadkami and Jog [1986] have reported on PPS/HDPE blends. The degree of crystallinity of HDPE was reduced when HDPE was the minor phase. Lurthermore, the T shifted to somewhat lower temperatures (by about 5°C) but only in those blends with a low HDPE content. Isothermal crystallization half-times for HDPE in its blends with PPS decreased as the HDPE content decreased, indicating an enhanced nucleation from the solidified PPS interfaces. 

PP-MA/EVAl maleic anhydride grafted PP HDPE lameUas Kamal et al., 1995 Garmabi... 

In three-component blends (PP/HDPE/EPDM), HDPE was reported to be within the EPDM phase, regardless of order of addition. It was assumed that HDPE acts as a viscosity modifier and improves EPDM dispersability [Thamm, 1977]. 

Blends of polyolefins (e.g., HPDE/LDPE, LDPE/ ethylene copolymers, PP/EPDM, PP/HDPE/EPDM, HDPE/butyl rubber) have been commercial since the late 1960 s and early 1970 s. Specific film formulations were commonly based on polyolefin blends to achieve the proper balance of processing, environmental stress crack resistance, modulus, toughness, cling, transparency, filler acceptance, printability, tear resistance, shrinkage characteristics, and permeability. Ethylene-propylene mbber (EPR, EPDM) was commonly incorporated into polypropylene as an impact modifier at moderate levels and as a flexibilizer at high levels. One of... 

For each of the following polymers, indicate whether they are addition or condensation polymers LLDPE, nylon 6,6, PVC, PC, PAN, PP, HDPE, PET, LDPE, and PVDC. Write their chemical structures. 

Property Rel. hum. % Phys. unit PP HDPE PTFE PVC PS PVAL... 

It was proposed [85] that PLA could improve the properties of PP/HDPE/EVA blends. The mechanical properties showed that the polymer blend had optimum tensile and burst strengths at 4 wt% PLA incorporated into the PP/HDPE/EVA blend. The tear strength decreased with increasing PLA content in both the machine and the transverse directions. The friction coefficient was found to be the lowest at 4 wt% PLA... 

Uses Antioxidant, metal deactivator for polymers, PP, HDPE, LDPE, some thermoplastic elastomers used as primary insulation in wire/cable applies., EPDM, peroxide- and radiation-crosslinked PE, nylon, polyacetal, polybutene, PU, styrenic copolymers, unsat. rubber, PVC, PVB, hot-melt and sol n. adhesives, powd. coatings, metal coatings, rubber/plas-tic gaskets, plastic fabricated parts in contact with catalytic metals, oils/ lubricants in contact with metals, food pkg. 

Chem. Descrip. Dioctadecyl thiodipropionate CAS 693-36-7 EINECS/ELINCS 211-750-5 Uses Antioxidant for polymers, esp. PP, HDPE, LDPE, LLDPE, PS,ABS, PMMA, PA, PET, PBT, PC, POM, PU, in resinous/polymeric food-con-tact coatings, migrating from food pkg. 

Chem. Descrip. 2 -Ethylhexyl 2-cyano-3,3-diphenylacrylate CAS 6197-30-4 EINECS/ELINCS 228-250-8 Uses UV absorber for polymers, esp. PVC, PET, PP, HDPE, LDPE, LLDPE, PMMA, PUR, BR, SBR, coalings Prr rerties Lt. yel. liq. m.w. 361.5 vise. 1900 + 300 cps Seesorb 704 [Shipro Kasei Kaisha]... 

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