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Polymer Melt Rheology A For Indu Free 👍

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Polymer Melt Rheology A For Indu

Plastic compounds (homopolymer and copolymer), semi- or pseudo-phases, and additives are used. The selection of additives is the crux of the problem. An example of the art of the problem is given in terms of the following points: 1. The viscosity of a mixture is the linear sum of the viscosity of the components. 2. The viscosity of the mixture can be predicted by multiplying viscosity values of the components. 3. In any mixture, it is not possible to predict the viscosity from the knowledge of viscosity of the components.

4. The chemical composition of the mixture can lead to variations in viscosity. 5. The viscosity of a mixture is dependent on the time of measurement. 6. Using only a single flow measurement technique can lead to errors in viscosity determination.
8. Considerate analytical data on the viscosity of a mixture are not adequate for estimating the viscosity of a mixture. 9. More than 10% of the surface of a melt is in contact with the cooling surfaces.
10. A system consisting of two components which are a combination of A and B and A and B has more viscosity than a pure B. 11. According to Jantzen and Rosenbugh, if a body B is formed in a mould C from a polymer mixture A/B, then C has a lower melt viscosity than A alone.
12. As the viscosity of a polymer decreases, there is a sharp increase in the formation of surface defects. 13. The viscosity of a molten mass can vary greatly depending on the shape of the shape of the molten mass. 14. A smaller amount of metering die orifice can give a higher viscosity melt.
15. In the case of non-Newtonian shear-thinning materials, the viscosity cannot be predicted from the single viscosity measurement technique. 16. The shape of the contour of the flow (parabolic, hyperbolic etc.) may influence the viscosity of the material.
17. The skin friction and in-house viscosity of molten metal flow can be correlated. 18. A mixture of two polymers can give a similar viscosity to that of a polymer of higher molecular weight. 19.

In many applications, a polymeric material is considered to be a two-phase, or composite, system in which the