Abstract
The microstructure–sealing performance linkages of linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) blends using thermo-rheological tools are discussed. The effect of molecular architecture in metallocene catalyzed LLDPE (mLLDPE), Ziegler–Natta catalyzed LLDPE (ZN-LLDPE) on the miscibility, and rheological behavior of the blends with LDPE is shown. Even though the macro parameters like density, melt flow rate of the LLDPEs are comparable, subtle differences in the microstructure manifested by comonomer type and its distribution across molecular weight affects the sealing performance of the LLDPE/LDPE blends. For LLDPE matrix, tailor-made comonomer distribution affording thinner lamellas (viz., thickness <11.8 nm) is more critical to sealing process than having total higher comonomer content. For LLDPE/LDPE blends, the thicker lamellae of main chain polymer of LDPE co-crystallize with homo-polyethylene like fraction of LLDPE. The co-crystallization of LLDPE and LDPE helps to achieve hot tack sealing at lower percentage of molten polymer and it appears to be the dominating factor over diffusion of polymer chains across the melt interface to achieve sealing.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.