High density polyethylene experimental

Fig. 10.8. Calculation of the solubility of gases in 24 different polymers, ranging from polyethylene to nitrocellulose [120], One polymer-specific constant has to be adjusted in order to achieve good results. Experimental data are taken from Pauli [121] (HDPE = high density polyethylene, POP = polyfoxyethylene glycol), PDMS = poly(dimethylsiloxane), PTFE = poly(tetrafluoroethylene)).

E. M. Mount, III, The Melting of High Density Polyethylene on a Heated, Moving Metal Surface—A Comparison of Experimental and Theoretical Results, M.S. thesis, Rensselaer Polytechnic Institute, Troy, NY, (1976). 

A test set of 6 to 13 aroma compound partition coefficients between different food contact polymers (low density polyethylene (LDPE), high density polyethylene (HDPE) polypropylene (PP), polyethylene terephthalate (PET), polyamide (PA)) and different food simulant phases (water, ethanol, aqueous ethanol/water mixtures, methanol, 1-propanol) were taken from the literature (Koszinowski and Piringer, 1989, Baner, 1992, Franz, 1990, Koszinowski, 1986, Franz, 1991, Baner, 1993, Piringer, 1992). Table 4-2 shows the test set of 13 different aroma compounds, with their properties and their structures. The experimental data were compared to estimations using different estimation methods of UNIFAC-FV, GCFLORY (1990), GCFLORY (1994) and ELBRO-FV. 

The composition of feed polymers also has an important effect on the properties of products. In the experimental work of Miskolczi et al. commercial waste plastics from the packaging, electronic and automotive industry and the agriculture were used as raw materials. The samples contained high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), ethylene-propylene copolymer (EPC), polystyrene (PS), polyamide 6.6 (PA 6.6) and polyvinyl chloride (PVC). 

Figure 22 Experimental data and theoretical curves (expression 4-21) of the complex shear modulus of commercial polypropylene (M = 348 500, M /Mn = 6.1) and high density polyethylene (M = 210 000, = 11.7) [19]...

Melt fracture has been a very perplexing but fascinating problem ever since it was discovered. Another problem that seems to have the same degree of perplexity and fascination is draw resonance. Both are instabilities in polymer flows. (Draw resonance may also occur in Newtonian fluids.) Draw resonance is a periodic variation in the diameter of a spinning thread line above a critical drawdown ratio. Polypropylene and high-density polyethylene are both particularly susceptible to draw resonance. Petrie and Denn have presented a comprehensive review of the numerous theoretical and experimental studies of draw resonance conducted prior to 1976 [99]. 

The economic viability of this process, however, will depend on the attainable polymer /solvent ratio. For example, it has been found that under experimental conditions lOOg of high density polyethylene (HOPE) may be dissolved in one litre of toluene before the solution becomes too viscous to process [12]. Wietek claims that energy costs for a pilot plant are similar to those of mechanical recycling when running with high polymer/solvent ratios. The financial breakeven point for a commercial plant of this type is calculated to be roughly 3,000 tonnes per year [13]. 

Figure 7.10 High-density polyethylene filaments extensional ( 3), transverse ( 1) and torsional moduli (G) comparison between experimental results and simple aggregate theory for 3 and 1 ((a) and (b)) and for G (c)...

It is important to observe that the experimental framework used in this work was designed to allow a comparative study of the mechanical strength properties of non-irradiated and irradiated samples of a specific high-density polyethylene material. Thus, the validity of the data and conclusions obtained is limited by the assumptions and material used. In order to produce more general data, it is desirable to make use of other complementary tests to better characterize the changes in the microstructure of the material due to the application of gamma radiation. 

Fig. 9. Comparison between model prediction and experimental findings for high density polyethylene/polystyrene blend, PE/FS = 95/5 (vol%) compounded at the screw speed N = 150 rpm with an output of Q = 10 kg/h.

FIGURE 2.11 LLE of high-density polyethylene (HDPE)-l-heptanol and HDPE-l-nonanol. Experimental data [86] (points) and NRHB calculations (lines). 

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