02609nas a2200337   4500008004100000022001400041245017500055210006900230260000800299300002100307490000700328520146600335653001901801653003301820653001401853653000901867653003001876653001301906653001901919653001701938653001301955653001401968100002201982700002102004700002002025700002902045700002502074700002302099700001802122856013102140       2021                        eng d  a8756-087900aControlling draw resonance during extrusion film casting of nanoclay filled linear low-density polyethylene: an experimental study and numerical linear stability analysis0 aControlling draw resonance during extrusion film casting of nano  cJUL  a87560879209784430 v373 a<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>
10aDraw resonance10aextensional strain hardening10aExtrusion10aFilm10ahydrodynamic interactions10aNanoclay10aNanocomposites10aPolyethylene10aRheology10astability1 aRokade, Dhammaraj1 aChougale, Sanket1 aPatil, Prashant1 aBhattacharjee, Tanushree1 aGawande, Dnyaneshwar1 aPol, Harshawardhan1 aDhadwal, Renu  uhttps://library.ncl.res.in/content/controlling-draw-resonance-during-extrusion-film-casting-nanoclay-filled-linear-low-density02655nas a2200289   4500008004100000022001400041245013800055210006900193260000800262300001200270490000700282520171900289653001902008653001402027653000902041653001702050653002402067653002002091653001202111653001002123653002102133100002202154700002002176700002302196700002302219856012302242       2023                        eng d  a8756-087900aRheology and processing study on controlling material and process defects in polymer melt extrusion film casting using polymer blends0 aRheology and processing study on controlling material and proces  cAPR  a211-2400 v393 a<p>
	The primary objective of this research paper is to control the material and process defects in polymer melt extrusion film casting (EFC) process for linear chain architecture polyethylene (PE) resins through polymer blending methodology. Extrusion film casting is a well-known industrially important manufacturing process that is used to manufacture thousands of tons of polymer/plastic films/sheets and coated products. In this research, the necking defect in an EFC process has been studied experimentally for a linear low density polyethylene (LLDPE) resin and attempts have been made to control its necking by blending in a long chain branched (LCB) low density polyethylene (LDPE) resin. The blending methodology is based on the understanding that a LDPE resin displays enhanced resistance to necking as compared to the LLDPE resin. It is found that added LDPE resin enhances necking resistance for the primary LLDPE resin. Further, as the LDPE concentration increases in the blend formulation, the necking is further reduced as compared to pure LLDPE. Analogous to past studies on EFC of linear and long chain branched architecture containing PEs, it is observed that as the LDPE is increased in the blend formulations, the formulations displayed enhanced melt elasticity and extensional strain hardening in rheological studies. It is concluded from this study that polyethylene resins having linear chain architecture can be made amenable to enhanced resistance to necking using appropriate amount of a long chain branched resins. Finally, process defects such as the draw resonance onset could be shifted to higher draw ratios as the LDPE level is increased in the LLDPE-LDPE blend formulation.</p>
10aDraw resonance10aExtrusion10aFilm10alinear chain10along-chain branched10amelt elasticity10aNecking10aonset10astrain hardening1 aRokade, Dhammaraj1 aPatil, Prashant1 aNandimath, Sheetal1 aPol, Harshawardhan  uhttps://library.ncl.res.in/content/rheology-and-processing-study-controlling-material-and-process-defects-polymer-melt