@article {43561,
	title = {Controlling necking in extrusion film casting using polymer nanocomposites},
	journal = {Journal of Macromolecular Science Part B-Physics},
	volume = {56},
	year = {2017},
	month = {FEB},
	pages = {213-233},
	abstract = {The research described was concerned with the effect of layered-silicate-based organically modified nanoclay fillers on controlling the extent of necking in a polymer melt extrusion film casting (EFC) process. We show that a linear polythylene resin (such as a linear low-density polyethylene-LLDPE) filled with a very low percentage of well-dispersed (or intercalated) nanoclay displays an enhanced resistance to the necking phenomenon. In general, melt-compounded nanoclay-filled LLDPE resin formulations displayed a higher final film width (less necking), thus a lower final film thickness (greater draw down for the same draw ratio), and cooled down faster when compared to the base LLDPE resin. Incorporation of nanoclay filler in the mainly linear chain LLDPE resin led to significant modification of the melt rheological properties that, in turn, affected the melt processability of these formulations. Primarily, the intercalated nanoclay-filled LLDPE formulations displayed the presence of strain-hardening in unaxial extensional rheology. Additionally, the presence of well-dispersed nanoclay in the LLDPE resin led to a display of prominent extrudate swell indicating the presence of melt elasticity in such formulations. The presence of melt elasticity, as shown by shear rheology and strain-hardening, observed by uniaxial extensional rheology, contributed to the LLDPE nanoclay formulations displaying an enhanced resistance to necking for these films. It can be concluded that linear chain polymers susceptible to necking in an EFC process can be made more resistant to such necking by using nanoclay fillers at very low levels of loading.},
	doi = {10.1080/00222348.2017.1289797},
	author = {Rokade, Dhammaraj and Azad, Lal B. and Poddar, Suparna and Mishra, Satyendra and Pol, Harshawardhan V. and Shukla, Rishab}
}
@article {46603,
	title = {Controlling draw resonance during extrusion film casting of nanoclay filled linear low-density polyethylene: an experimental study and numerical linear stability analysis},
	journal = {Journal of Plastic Film \& Sheeting},
	volume = {37},
	year = {2021},
	month = {JUL},
	pages = {8756087920978443},
	type = {Article},
	abstract = {<p>Commercially important extrusion film casting (EFC) processes for manufacturing plastic films or sheets are hampered by several instabilities that severely limits their productivity. In this research we focussed on one important instability: the draw resonance that occurs during the EFC process mainly under extensional flow conditions. Draw resonance is the sustained periodic oscillations in the film dimensions, notably film width and thickness, when the process operates beyond a critical draw ratio (CDR). In this research our goal was to reduce this draw resonance instability by incorporating well dispersed nanoclay fillers in a base polymeric resin (such as a linear low density polyethylene - LLDPE) to determine how these nanocomposite (NC) formulations can prevent or reduce the draw resonance defect. EFC experiments were conducted on the base resin and on the NC formulations under non-isothermal conditions to determine the onset of the draw resonance experimentally. Conventional linear stability analysis was performed to determine the onset of the draw resonance defect numerically. Numerical predictions for the onset of draw resonance were in qualitative agreement with our experimental data. Our results showed that incorporating appropriate nanoclay concentrations in a base polymeric resin indeed enhanced the EFC process stability for those polymer formulations and thus can have important economic implications for processors.</p>
},
	keywords = {Draw resonance, extensional strain hardening, Extrusion, Film, hydrodynamic interactions, Nanoclay, Nanocomposites, Polyethylene, Rheology, stability},
	issn = {8756-0879},
	doi = {10.1177/8756087920978443},
	author = {Rokade, Dhammaraj and Chougale, Sanket and Patil, Prashant and Bhattacharjee, Tanushree and Gawande, Dnyaneshwar and Pol, Harshawardhan and Dhadwal, Renu}
}
