Thermoplastic polymeric nanocomposite films and related methods
The disclosure relates to a nanocomposite polymeric film including a thermoplastic polymer matrix such as polypropylene or other polyolefin, a coupling agent-modified organoclay reinforcement, and a polymeric compatibilizer bound to the coupling agent-modified organoclay, in particular as a thin film with controllable thicknesses. The disclosure further relates to masterbatch additives formed from the coupling agent-modified organoclay and the polymeric compatibilizer bound to the coupling agent-modified organoclay as well as related methods for making the nanocomposite polymeric film and/or processing recycled plastics. The inclusion of the coupling agent-modified organoclay reinforcement improves the mechanical properties of the nanocomposite polymeric film and the rheological properties of polymer melts including the nanocomposite polymeric film components. The coupling agent-modified organoclay leads to strain-hardening behavior for the polymer melts, which in turn can improve extensional viscosity values and melt processability for film blowing.
1. A nanocomposite polymeric film comprising:
(a) a thermoplastic polymer matrix;
(b) a coupling agent-modified organoclay, wherein the coupling agent is covalently bonded and hydrogen-bonded to both edges and faces of the organoclay; and
(c) a polymeric compatibilizer bound to the coupling agent-modified organoclay.
2. The nanocomposite polymeric film of claim 1 , wherein the thermoplastic polymer matrix comprises one or more of a polyolefin, polyacrylate, poly(acrylonitrile-butadiene-styrene), poly(lactic acid), polybenzimidazole, polycarbonate, polyether sulfone, polyetherether ketone, polyetherimide, polyphenylene oxide, polyphenylene sulfide, polystyrene, polyvinyl chloride polyester, polyamide, copolymers thereof, and combinations thereof.
3. The nanocomposite polymeric film of claim 1 , wherein the thermoplastic polymer comprises a polyolefin selected from the group consisting of polyethylene, polypropylene, polymethylpentene, polybutene, block copolymers thereof, random copolymers thereof, and mixtures thereof.
4. The nanocomposite polymeric film of claim 1 , wherein the thermoplastic polymer comprises polypropylene.
5. The nanocomposite polymeric film of claim 1 , wherein the coupling agent comprises a silane coupling agent.
6. The nanocomposite polymeric film of claim 1 , wherein the organoclay comprises a smectite clay.
7. The nanocomposite polymeric film of claim 1 , wherein the coupling agent-modified organoclay has an interlayer spacing between adjacent organoclay platelets of at least 0.1 nm greater than the interlayer spacing of a corresponding organoclay without the coupling agent modification.
8. The nanocomposite polymeric film of claim 1 , wherein the polymeric compatibilizer is bound to the coupling agent-modified organoclay at the edges and the faces of the organoclay.
9. The nanocomposite polymeric film of claim 1 , wherein the polymeric compatibilizer comprises a maleate functional group.
10. The nanocomposite polymeric film of claim 1 , wherein the polymeric compatibilizer comprises a thermoplastic polymer and a modifier functional group for binding to the coupling agent-modified organoclay.
11. The nanocomposite polymeric film of claim 1 , wherein the film has a thickness of 1 mil or less.
12. The nanocomposite polymeric film of claim 1 , wherein the film has a thickness ranging from 0.2 mil to 0.8 mil.
13. The nanocomposite polymeric film of claim 1 , wherein the film has a thickness relative standard deviation (RSD) of 25% or less.
14. The nanocomposite polymeric film of claim 1 , wherein the ratio of the polymeric compatibilizer to the coupling agent-modified organoclay ranges from 0.1 to 10.
15. The nanocomposite polymeric film of claim 1 , wherein the combined amount of the polymeric compatibilizer and the coupling agent-modified organoclay in the nanocomposite polymeric film ranges from 2 wt. % to 50 wt. %.
16. The nanocomposite polymeric film of claim 1 , wherein the amount of the coupling agent-modified organoclay in the nanocomposite polymeric film ranges from 0.5 wt. % to 15 wt. c/o.
17. The nanocomposite polymeric film of claim 1 , wherein the amount of the thermoplastic polymer in the nanocomposite polymeric film ranges from 50 wt. % to 98 wt. %.
18. A nanocomposite polymeric film comprising:
(a) a thermoplastic polymer matrix comprising polypropylene;
(b) a silane coupling agent-modified organoclay, wherein (i) the silane coupling agent is covalently bonded and hydrogen-bonded to both edges and faces of the organoclay, and (ii) the silane coupling agent-modified organoclay has an interlayer spacing between adjacent organoclay platelets of at least 0.1 nm greater than the interlayer spacing of a corresponding organoclay without the coupling agent modification; and
(c) a maleated polyolefin polymeric compatibilizer bound to the silane coupling agent-modified organoclay;
wherein:
(i) the film has a thickness of 1 mil or less; and
(ii) the film has a thickness relative standard deviation (RSD) of 25% or less.
19. A masterbatch additive comprising:
(a) a coupling agent-modified organoclay, wherein (i) the coupling agent is covalently bonded and hydrogen-bonded to both edges and faces of the organoclay, and (ii) the coupling agent-modified organoclay has an interlayer spacing between adjacent organoclay platelets of at least 0.1 nm greater than the interlayer spacing of a corresponding organoclay without the coupling agent modification; and
(b) a polymeric compatibilizer bound to the coupling agent-modified organoclay.
20. A method for making a nanocomposite polymeric film, the method comprising: (a) providing a polymer melt comprising: (i) a thermoplastic polymer, (ii) a coupling agent-modified organoclay, wherein the coupling agent is covalently bonded and hydrogen-bonded to both edges and faces of the organoclay, and (iii) a polymeric compatibilizer bound to the coupling agent-modified organoclay;
(b) blowing or extruding and stretching the polymer melt to form the nanocomposite polymeric film.
21. The method of claim 20 , wherein providing the polymer melt comprises melt blending a masterbatch additive comprising the coupling agent-modified organoclay and the polymeric compatibilizer with the thermoplastic polymer.
22. The nanocomposite polymeric film of claim 1 , wherein the organoclay comprises a layered smectite clay and organophilic ions exchanged into interlayer galleries of the layered smectite clay.