US-12623430-B2 - Thermally stable multilayer pipe

US12623430B2US 12623430 B2US12623430 B2US 12623430B2US-12623430-B2

Abstract

Multilayer pipe comprising at least a first layer and a second layer, wherein the first layer is comprised a first polymer have a first thermal stability, and the second layer is comprised of a second polymer having a second thermal stability that is improved relative to said first thermal stability. In one exemplary embodiment, the first layer is comprised of PVC or CPVC, and the second layer is comprised of polycarbonate.

Inventors

Vickram Dhanapal
Brian Davis
Matthew Thomas FENNEMAN
Michael Kenneth DAVIS

Assignees

Engineered Profiles LLC

Dates

Publication Date: 20260512
Application Date: 20220505

Claims (14)

1 . A pipe consisting of: an outermost layer of a polyvinyl chloride material; and a second layer adjoined and positioned inwardly relative to said outermost layer, said second layer selected from the group consisting of a chlorinated polyvinyl chloride material and a polycarbonate material; wherein neither said polyvinyl chloride material of said outermost layer nor said chlorinated polyvinyl chloride material or said polycarbonate material of said second layer are foamed; wherein said pipe has been extruded such that said pipe has a smooth outer surface; and wherein said pipe has improved thermal stability such that said pipe has improved resistance to a permanent property change caused solely by heat as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
2 . The pipe of claim 1 wherein said pipe has a lower coefficient of linear thermal expansion as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
3 . The pipe of claim 1 wherein said pipe has reduced thermal shrinkage as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
4 . The pipe of claim 1 wherein said pipe has a higher heat distortion temperature as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
5 . The pipe of claim 1 wherein said pipe has reduced thermal shrinkage and a higher heat distortion temperature as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
6 . The pipe of claim 1 wherein said pipe has a lower coefficient of linear thermal expansion and a higher heat distortion temperature as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
7 . The pipe of claim 1 wherein said pipe has a lower coefficient of linear thermal expansion and reduced thermal shrinkage as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
8 . The pipe of claim 1 wherein said pipe has a lower coefficient of linear thermal expansion, reduced thermal shrinkage, and a higher heat distortion temperature as compared to a pipe having a same shape and dimensions and comprised of only a same polyvinyl chloride material as said pipe.
9 . The pipe of claim 1 wherein said second layer consists of said chlorinated polyvinyl chloride material.
10 . The pipe of claim 1 wherein said chlorinated polyvinyl chloride material or said polycarbonate material of said second layer comprises glass filler in an amount up to 35 wt. % of said second layer.
11 . The pipe of claim 10 wherein said chlorinated polyvinyl chloride material or said polycarbonate material of said second layer comprises said glass filler in an amount between about 9 wt. % and 30 wt. % of said second layer.
12 . The pipe of claim 1 wherein said second layer consists of said polycarbonate material.
13 . The pipe of claim 12 wherein said polycarbonate material of said second layer comprises glass filler in an amount up to 35 wt. % of said second layer.
14 . The pipe of claim 13 wherein said polycarbonate material of said second layer comprises said glass filler in an amount between about 9 wt. % and 30 wt. % of said second layer.

Description

This application claims the priority benefit of U.S. Provisional Application No. 63/184,303, filed May 5, 2021, which is hereby incorporated in its entirety. BACKGROUND AND SUMMARY OF THE INVENTION Exemplary embodiments of the present invention relate generally to pipe. Plastic pipe is commonly made of polyvinyl chloride (PVC) or chlorinated polyvinyl chloride (CPVC). PVC or CPVC may provide beneficial properties for pipe such as resistance to corrosion and degradation. Both materials also offer good resistance to heat. In particular, PVC may have a max functional temperature of about 140° Fahrenheit, and CPVC may have a max functional temperature of about 200° Fahrenheit. However, both PVC and CPVC are expensive, and the price of CPVC is typically much higher than for PVC. Therefore, there is a need for a cost-effective substitute for PVC and CPVC, particularly for plastic pipe, while also providing improved or similar thermal stability relative to PVC and CPVC, particularly as used for traditional plastic pipe. Other types of pipe may be comprised of polyethylene, polypropylene, or other polymers. These other polymers may also be expensive and/or lack in thermal stability. As such, there is also a need for a cost-effective substitute for any of these polymers, while also providing improved or similar thermal stability relative to those polymers. An exemplary embodiment may address some or all of the shortcomings of the known art. In an exemplary embodiment, a pipe comprises at least a first layer and a second layer, wherein the first layer is comprised a first polymer have a first thermal stability, and the second layer is comprised of a second polymer having a second thermal stability that is improved relative to said first thermal stability. In at least one exemplary embodiment, at least a first layer may comprise PVC, CPVC, acrylonitrile butadiene styrene (ABS), polyethylene, polypropylene, or other similar or suitable material. The second layer may comprise polycarbonate, acrylic, acrylonitrile styrene acrylate, acrylonitrile butadiene acrylate, ABS, CPVC, nylon, or other similar or suitable material having improved thermal stability relative to the polymer of the first layer. Some exemplary embodiments may also comprise at least a third layer. For instance, by way of example, one particularly useful embodiment may comprise PVC or CPVC as an outer layer, polycarbonate as a middle layer, and PVC or CPVC as an inner layer. In one example, an embodiment may provide improved thermal stability characteristics compared to an otherwise similar component comprising only the aforementioned first layer and/or compared to an otherwise similar traditional component that does not have the aforementioned second layer. In another example, an embodiment may provide the same, similar, or improved thermal stability characteristics at a reduced cost compared to an otherwise similar component comprising only the aforementioned first layer and/or compared to an otherwise similar traditional component that does not have the aforementioned second layer. In one exemplary embodiment, a plastic pipe comprises at least one layer (preferably an outer layer) comprised of PVC or CPVC, and at least one layer (preferably an intermediate or inner layer) comprised of polycarbonate. While plastic pipe is commonly made of PVC or CPVC, other exemplary embodiments of the present invention may have at least one layer (preferably an outer layer) comprised of polyethylene or polypropylene, and at least one layer (preferably an intermediate or inner layer) comprised of nylon. In any of these embodiments, the resulting plastic pipe may have improved thermal stability characteristics, or the same, similar, or improved thermal stability characteristics at a reduced cost, compared to an otherwise similar component comprised only of PVC, CPVC, polyethylene, or polypropylene. In an exemplary embodiment, the first, second, and/or any additional layer may have at least one additional filler, additive, or doping material mixed in with the polymeric material. Some types of filler material include, but are not limited to, glass, talc, fibrous material, chemicals, metals, other mineral fillers, and other organic or inorganic materials. Other materials or material layers may be used if desired and compatible with at least one of the aforementioned layers. The filler, additive or doping materials may be of any material that is compatible with the material of the layer in which the filler is placed. Additionally, users may choose which filler, additive or doping materials to use based on the properties that will be enhanced or added to the final material. One or more filler material may be used. In particular, it may be desired that additives, fillers, or doping materials selected be useful in improving (or at least not diminishing) the thermal stability of a pipe. Thermal stability is a substance's resistance to permanent property changes caused solely by