Delamination-resistant multilayer container, preform and method of manufacture
View Patent ↗A plastic container or preform includes a multilayer wall having at least one layer of polyester resin, at least one layer of barrier resin, and an adhesion-promoting material blended with the barrier resin and/or the polyester resin to promote bonding between the barrier and polyester layers. The adhesion-promoting material includes an organometallic coupling agent based upon titanium, zirconium or aluminum. The organometallic coupling agent preferably has an amino end group with an affinity for carboxylic end groups in the polyester, and preferably is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamino) ethyl titanate, zirconate and aluminate. Coupling agents based upon titanium and zirconium are particularly preferred for containers and preforms having a clear (non-colored) wall.
1. A plastic container having a multilayer wall that includes:
at least one layer of polyester resin,
at least one layer of barrier resin, and
an adhesion-promoting material blended with said barrier resin and/or said polyester resin to promote bonding between said barrier and polyester layers, said adhesion-promoting material including an organometallic coupling agent based upon titanium, zirconium or aluminum.
2. The container set forth in claim 1 wherein said polyester resin is selected from the group consisting of: PET, PEN, blends or copolymers of PET and PEN, and process regrind consisting essentially of PET, PEN, or blends or copolymers of PET and PEN.
3. The container set forth in claim 1 wherein said barrier resin is selected from the group consisting of: EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof.
4. The container of claim 1 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
5. The container set forth in claim 1 wherein said organometallic coupling agent includes an amino end group.
6. The container set forth in claim 5 wherein said organometallic coupling agent is selected from the group consisting of: alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
7. The container set forth in claim 6 wherein said coupling agent consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.
8. A plastic container having a multilayer wall that includes:
at least one layer of polyester resin selected from the group consisting of PET, PEN, blends or copolymers of PET and PEN, and process regrind that consists essentially of PET, PEN, or blends or copolymers of PET and PEN,
at least one layer of barrier resin selected from the group consisting of EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof, and
an organometallic coupling agent blended in said at least one layer of barrier resin to promote bonding between said barrier and polyester layers, said organometallic coupling agent having an amino end group that has an affinity for carboxylic and groups in the polyester resin and being selected from the group consisting of organo titanate, organo zirconate and organo aluminate.
9. The container of claim 8 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
10. The container set forth in claim 8 wherein said coupling agent is selected from the group consisting of alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
11. The container set froth in claim 10 wherein said coupling agent consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.
12. A method of making a multilayer plastic container that includes:
(a) blending an organometallic coupling agent based on titanium, zirconium or aluminum with a barrier resin, and
(b) forming a preform in which the blend formed in step (a) is in layers alternating with layers of polyester resin, and in which said coupling agent promotes bonding between said barrier resin and said polyester resin.
13. The process set forth in claim 12 further including: (c) blow molding the preform formed in step (b) into a hollow plastic container.
14. The method of claim 12 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
15. The method set forth in claim 12 wherein said step (b) is carried out while said blend formed in said step (a) and said polyester resin are in melt phase.
16. The method set forth in claim 15 wherein said step (b) is carried out by a process selected from the group consisting of simultaneously injection molding said polyester resin and said barrier resin blend, sequentially injection molding said polyester resin and said barrier resin blend, overmolding sequential layers of said polyester resin and said barrier resin blend, compression molding a mold charge that includes said polyester resin and said barrier resin blend, and extruding a hollow tube that includes alternate layers of said polyester resin and said barrier resin blend.
17. The method set forth in claim 12 wherein said coupling agent has an amino end group.
18. The method set forth in claim 17 wherein said organometallic coupling agent is selected from the group consisting of: alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
19. The method set froth in claim 18 wherein said coupling agent consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.
20. The method set forth in claim 17 wherein said polyester resin is selected from the group consisting of PET, PEN, blends or copolymers of PET and PEN, and process regrind consisting essentially of PET, PEN, or blends or copolymers of PET and PEN.
21. The method set forth in claim 17 wherein said barrier resin is selected from the group consisting of: EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof.
22. A preform for blow molding a plastic container having a multilayer wall, which includes:
at least one layer of polyester resin,
at least one layer of barrier resin, and
an adhesion-promoting material blended with said barrier resin and/or said polyester resin to promote bonding between said barrier and polyester layers, said adhesion-promoting material including an organometallic coupling agent based upon titanium, zirconium or aluminum.
23. The preform set forth in claim 22 wherein said polyester resin is selected from the group consisting of: PET, PEN, blends or copolymers of PET and PEN, and process regrind consisting essentially of PET, PEN, or blends or copolymers of PET and PEN.
24. The preform set forth in claim 22 wherein said barrier resin is selected from the group consisting of: EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof.
25. The preform of claim 22 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
26. The preform set forth in claim 22 wherein said organometallic coupling agent includes an amino end group.
27. The perform set forth in claim 26 wherein said organometallic coupling agent is selected from the group consisting of: alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
28. The preform set forth in claim 27 wherein said coupling agent consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.
29. A preform for blow molding a plastic container having a multilayer wall, which includes:
at least one layer of polyester resin selected from the group consisting of PET, PEN, blends or copolymers of PET and PEN, and process regrind that consists essentially of PET, PEN, or blends or copolymers of PET and PEN,
at least one layer of barrier resin selected from the group consisting of EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof, and
an organometallic coupling agent blended in said at least one layer of barrier resin to promote bonding between said barrier and polyester layers, said organometallic coupling agent having an amino end group that has an affinity for carboxylic end groups in the polyester resin and being selected from the group consisting of organo titanate, organo zirconate and organo aluminate.
30. The preform of claim 29 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
31. The preform set forth in claim 29 wherein said coupling agent is selected from the group consisting of ethyl alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
32. The preform set forth in claim 31 wherein said coupling agent consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.
33. A plastic article of manufacture having a multilayer wall that includes:
at least one layer of polyester resin,
at least one layer of barrier resin, and
an adhesion-promoting material blended with said barrier resin to promote bonding between said barrier and polyester layers, said adhesion-promoting material including an organometallic coupling agent based upon titanium, zirconium or aluminum.
34. The article set forth in claim 33 wherein said polyester resin is selected from the group consisting of: PET, PEN, blends or copolymers of PET and PEN, and process regrind consisting essentially of PET, PEN, or blends or copolymers of PET and PEN.
35. The article set forth in claim 30 wherein said barrier resin is selected from the group consisting of: EVOH, nylon, acrylonitrile copolymers, blends of EVOH and nylon, nanocomposites of EVOH or nylon and clay, blends of EVOH and an ionomer, acrylonitrile, cyclic olefin copolymers, polyglycolic acid, and blends thereof.
36. The article of claim 30 wherein the coupling agent is selected from the group consisting of neopentyl(diallyl)oxy, tri(N-ethylenediamine) titanate, neopentyl(diallyl)oxy, tri(N-ethylenediamine) zirconate and neopentyl(diallyl)oxy, tri(N-ethylenediamine) aluminate.
37. The article set froth in claim 33 wherein said organometallic coupling agent includes an amino end group.
38. The article set forth in claim 37 wherein said organometallic coupling agent is selected from the group consisting of: alkyl or allyl titanate, alkyl or allyl zirconate and alkyl or allyl aluminate.
39. The article set forth in claim 38 wherein said coupling agents consists essentially of alkyl or allyl titanate or alkyl or allyl zirconate.