Bonded Insulation Product Batt From Spent Carpet And Waste

Abstract

A thermal insulation batt is created from recycled carpet fibers and fire resistant cotton shoddy bonded by staples of bi-component fiber having a polyester core and low melting polymeric sheath. The low melting polymeric sheath melts at a temperature well below the melting or degradation temperature of any of the carpet fibers from the recycled carpets. Since the sheath has a small thickness, the amount of melt created is small and bonding occurs only between the bi-component staple fiber and adjacent carpet fiber or fire resistant cotton shoddy without melt overflow. The rigidized thermal insulation batt can be used in a building between studs and may be used in an automobile door for sound proofing. This product is particularly well suited for use as acoustic and thermal insulation in buildings as non-load bearing partitions in interior offices of commercial buildings. This bonded low density composite fibrous structure has fire retarding constituents incorporated within the batt to retard propagation of building fire. These stated uses are non-limiting; and other uses are contemplated, including automobile interior structures.

Claims

1) A rigid bonded thermal insulation fiber composite batt, comprising: a) clean carpet fiber extracted from used carpet; b) cotton shoddy impregnated with lire resistant chemicals; c) staples of bi-component fibers with polyester core and low melting polymeric sheath; d) said fibers uniformly mixed to distribute the staples of bi-component fibers and fire resistant shoddy within said carpet fiber; e) a mold filled with said air layering said uniformly mixed fibers as a loosely packed batt; and f) said batt being rigidized by heating the mold, melting said low melting polymeric sheath; whereby said rigid thermal insulation batt can be handled and cut to various sizes according to user needs.

2) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein the thermal insulation batt comprises recycled carpet fibers ranging from about 40-50 wt. %. fire retardant cotton shoddy ranging from about 40-50 wt. %, and resin binder in the form of bi-component polyester core fibers with a low melting polymeric sheath ranging from about 5-20 wt. %

3) The rigid bonded thermal insulation fiber composite batt as recited by claim 2, wherein the thermal insulation batt comprises recycled carpet fibers of about 42.5 wt. %, fire retardant cotton shoddy of about 42.5 wt. %, and resin binder in the form of bi-component polyester core fibers with a low melting sheath of about 15 wt. %

4) The rigid bonded thermal insulation, fiber composite batt as recited by claim 1, wherein said low melting polymeric sheath of bi-component polyester staple fiber is selected from modified copolyester with melting point 320? F., low molecular weight polyethylene with melting point 248-356? F. depending on molecular weight, polypropylene with melting point 266? F., polyolefin melting point 320? F. or polyethylene/vinyl acetate (Poly(EVA) and Poly(EVOH) with melting point 267? F.

5) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein said fire resistant chemical is ammonium sulfate.

6) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein said rigidization heat treatment is at about 350? F. to 375? C., melting the low melting polymeric sheath creating a bond between said bi-component polyester fiber and adjacent recycled carpet fiber or fire resistant shoddy without melt overflow.

7) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein said thermal insulation batt is used as insulation in between budding studs.

8) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein said thermal insulation batt is used as acoustic sound proofing.

9) The rigid bonded thermal insulation fiber composite batt as recited by claim 1, wherein said thermal insolation batt is used as insulation in automobile doors for acoustic sound proofing.

10) A method for manufacturing a thermal insulation batt from spent carpet fibers, comprising the steps of: a) harvesting carpet fibers from spent carpet by mechanical shearing or separation processing of chopped pieces of carpet; b) cleaning harvested carpet fibers of cotton, wool, nylon, polyester or other fibers; c) procuring tire resistant cotton shoddy soaked in ammonium sulfate saturated solution and dried; d) procuring staples of bi-component fibers with polyester core and low melting sheath polymer melting at a temperature below 350? F.; e) uniformly mixing carpet fibers, fire resistant cotton shoddy and staples of bi-component fibers; f) air layering the uniform mixture in a mold of the required size of insulating batt without applying compressive force; and g) heating the mold in the temperature range of 350 to 375? F. creating a bond between fibers that contact the bi-component fibers creating a batt that does not become soaked by melt flow maintaining insulation capability of rigid batt; whereby the insulting batt is cut to a required size for insulation in buildings between studs as well as in automobile doors, providing sound proofing.

11) The method of manufacturing thermal insulation batt from spent carpet fibers as recited by claim 9, wherein said low melting sheath polymer selected from modified copolyester, low molecular weight polyethylene, polypropylene, polyolefin and poly(ethylene/vinyl, acetate.

12) The method of manufacturing thermal insulation batt from spent carpet fibers as recited by claim 9, wherein said thermal insulation batt comprises recycled carpet fibers ranging from about 40-50 wt. %, fire retardant cotton shoddy ranging from about 40-50 wt. %, and resin binder in the form of bi-component polyester core fibers with a low melting polymeric sheath ranging from about 5-20 wt. %.

13) The method of manufacturing thermal insulation batt from spent carpet fibers as recited by claim 11, wherein said thermal insulation batt comprises recycled carpet fibers of about 42.5 wt. %, fire retardant cotton shoddy of about 42.5 wt. %, and resin binder in the form of bi-component polyester core fibers with a low melting polymeric sheath of about 15 wt. %.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0031] The invention will be more fully understood and further advantages will become apparent when reference is had to the following detailed description of the preferred embodiments of the invention and the accompanying drawing, in which:

[0032] FIG. 1 illustrates at 10 a schematic diagram of the steps in forming the insulating batt;

[0033] FIG. 2 illustrates at 20 a conventional method for separating carpet fibers from recycled carpets; and

[0034] FIG. 3 is a photograph of bond between a bi-component fiber and a recycled carpet fiber.

DETAILED DESCRIPTION OF THE INVENTION

[0035] This invention relates to forming a rigid bonded insulation batt made from carpet fiber of spent carpets. This invention has enormous impact on the environment since several million tons of spent carpets are discarded in landfills and these carpets do not readily degrade. Due to its low bulk density, carpet waste can be voluminous. Therefore, recycling of these carpets and rugs would have a significant impact on efforts to effectively reduce plastic components in municipal waste streams. Carpet scraps of the sort noted above, can prove to be a valuable resource if the plastic generated from recycling can be used for other useful applications rather than being discarded into municipal waste streams.

[0036] The present invention takes advantage of any carpet fiber to effectively bond forming a loosely bonded low density batt, which is thermally insulating due to trapping air pockets. The bonding process of the fibers should not result in excessive melt flow since this closes off air pockets, increasing thermal conduction and loss of insulation capability. The bonding between carpet fibers, fire resistant cotton shoddy and polyester bi-component staple fibers is accomplished by having a low melting polymeric sheath overcoat provided on the bi-component polyester fiber. Since the thickness of the low melting polymer provided on the polyester is carefully controlled by an extrusion process, the amount of melt available for bond creation is very carefully controlled and no melt overflow occurs compromising insulation properties of the insulation batt produced.

[0037] FIG. 1 illustrates at 100 the schematic diagram or the steps in forming the insulating batt. At step 101, clean recycled carpet fibers are collected. This process uses a rotary or planar shear to cut the carpet pile very near the carpet base as shown at 101a. The carpet fibers collected may be cotton fibers, wool fibers, nylon fibers, polyesters fibers, and the like. The fibers may be collected using a complex separation process, as detailed in U.S. Pat. No. 6,155,020. At step 102, cotton shoddy is soaked in saturated ammonium sulfate or other fire retardants and dried. At step 103, staples of bi-component fibers with polyester core are coated with a sheath of low melting polymers. The low melting polymer melts at a temperature lower than 360? F. Candidate low melting polymers for the sheath coating are modified copolyester, low molecular weight polyethylene, polypropylene, polyolefin and polyethylene/vinyl acetate. Modified copolyester coated staple polyester fiber is available from https://www.huvis.com/eng/product/prod_info.asp/num=0 1&f=21&s=4&t=50&p=110 under the trade name LM. Polyethylene or polypropylene coated staple fiber is available from https://www.huvis.com/eng/product/prod_info.asp/num=0 1&f=21&s=4&t=50&p=110.

[0038] FIG. 2 illustrates at 200 the conventional method for separating carpet fibers from recycled carpets. The process set forth in U.S. Pat. No. 6,155,020 to Deem (the '020 patent) may be utilized when preparing sorted carpet waste for the insulation Product. The '020 patent provides an economical and efficient insulation material formed from recycled carpet waste. The basic processing steps include: 1) the post consumer (i.e. waste) carpet in bailed or rolled form is first visually inspected and separated from heavily contaminated waste so as to provide good quality material for processing: 2) the material is then fed into the primary shredder so as to form strips of the waste carpel; 3) the waste carpet strips are then led onto a feed screen for the separation process by shifting some of the styrene butadiene rubber latex adhesive, calcium carbonate filler, and polypropylene backing from the polymeric face fibers; 4) the backing material separated from the screen feeder is transferred to the filter/receiver and the carpet strips are then, fed into a metal separator to remove any metals such as carpet staples, tacks, bailing wire, etc. 5) the carpet strips are then fed into the primary hammer mill to begin the reduction and dismantling of the carpet strips into a heterogeneous mixture of the carpet face fiber and backing. A step screener then separates the top screen into over-sized pieces and returns them back to the hammer mill for a second pass, while the middle screen collects the face tufts that are generally ? inch to 1 inch in length and have had the bulk of backing material removed; 6) this feed is then transferred where the material can be treated with disinfectant and/or fire retardant additives; 7) the treated face material, typically having an average bulk density of 3-4 lbs./ft.sup.3, is transferred to a tumble drying station where the material drying process is accelerated and the disinfectant and/or fire retardant additives may set into the carpet face material; 8) the carpet face material is then transferred to a final feed screen to remove any loose backing material that may remain or have been separated during the tumble drying operation; 9) this material is transferred to the filter/receiver; 10) the material is then fed to a packing machine for consumer insulation use or balled for other industrial uses.

[0039] FIG. 3 illustrates at 300 a photograph of the bond between a bi-component fiber and a recycled carpet fiber. The bi-component fiber is shown at 301. The recycled carpet fiber is shown at 302. The bond formed by the melting of the sheath of the bi-component fiber after heating is shown at 303. Note that the molten sheath polymer only tonus the bond without spilling everywhere.

[0040] Having thus described the invention in rather full detail, it will be understood that such detail need not be strictly adhered to, but that additional changes and modifications may suggest themselves to one skilled in the art, all falling within the scope of the invention as defined by the subjoined claims.