Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0203—Separating plastics from plastics
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0213—Specific separating techniques
  • B29B2017/0217—Mechanical separating techniques; devices therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0213—Specific separating techniques
  • B29B2017/0293—Dissolving the materials in gases or liquids
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2077/00—Use of PA, i.e. polyamides, e.g. polyesteramides or derivatives thereof, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
  • B29K2083/00—Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2031/00—Other particular articles
  • B29L2031/726—Fabrics

Definitions

• the present invention relates to a method for recycling airbag fabric.
• Airbag fabrics generally have a polyamide fabric as a base fabric, the surface of which is coated with a silicone resin for the purpose of improving heat resistance, airtightness, flame retardancy, etc. For this reason, when recycling airbag fabrics (particularly the polyamide resin constituting the base fabric), it has been necessary to remove the silicone resin from the polyamide fabric that is the base fabric.
• a method for recycling airbag fabric is known in which the airbag fabric is treated with an alkaline aqueous solution to remove the silicone resin from the base fabric. Specifically, a method is known in which the airbag fabric is immersed in an alkaline aqueous solution containing a tertiary amine and a surfactant, and then the silicone resin is removed by stirring and leaving the solution to stand (Patent Document 1).
• the present invention was made in consideration of the above circumstances, and its purpose is to provide a new method for recycling polyamide resin airbag fabric that does not require the use of an alkaline aqueous solution to remove silicone resin.
• airbag fabric can be recycled without using an alkaline aqueous solution by a method that includes a heat treatment step in which a polyamide resin airbag fabric having silicone resin applied to at least one side is contacted with H2O at a temperature of 160°C or higher and at or above the saturated water vapor pressure, and a recovery step in which the polyamide resin from which the silicone resin has been removed is recovered, and have completed the present invention.
• the gist of the present invention is as follows.
• [1] A polyamide resin airbag fabric having a silicone resin applied to at least one side thereof, A heat treatment step of contacting the mixture with H 2 O at a temperature of 160° C. or higher and at a pressure equal to or higher than the saturated water vapor pressure; and a recovery step of recovering the polyamide resin from which the silicone resin has been removed.
• [2] The method for recycling an airbag fabric according to [1], wherein in the heat treatment step, the treatment temperature is 170° C. or higher and 230° C. or lower, and the treatment pressure is 0.9 MPa or higher and 3.0 MPa or lower.
• [3] The method for recycling an airbag fabric according to [1] or [2], characterized in that in the heat treatment step, the treatment temperature is 170° C. or higher and 210° C. or lower, and the treatment pressure is 0.9 MPa or higher and 1.9 MPa or lower.
• [4] The method for recycling an airbag fabric according to any one of [1] to [3], characterized in that in the recovery step, the polyamide resin from which the silicone resin has been removed is peeled off and recovered by applying an external force.
• a recycled polyamide resin composition comprising, as at least a part of a raw material, a polyamide resin recovered by the recycling method according to any one of [1] to [4].
• An airbag base fabric comprising, as at least a part of a raw material, a polyamide resin recovered by the recycling method according to any one of [1] to [4].
• the present invention provides a new method for recycling airbag fabric made of polyamide resin that does not require an alkaline aqueous solution to remove silicone resin.
• the recycling method of the present invention does not use an alkaline aqueous solution or can reduce the amount of alkaline aqueous solution used, thereby suppressing damage to the polyamide resin caused by alkaline treatment and making it possible to easily recover polyamide resin from which the silicone resin has been removed using a process that places little strain on the environment.
• the method for recycling airbag fabric of the present invention includes a heat treatment step of contacting a polyamide resin airbag fabric having a silicone resin applied to at least one side with H2O at a temperature of 160°C or higher and at a saturated water vapor pressure or higher, and a recovery step of recovering the polyamide resin from which the silicone resin has been removed.
• the polyamide resin airbag fabric is brought into contact with H2O at a temperature of 160°C or higher and at a saturated water vapor pressure or higher, thereby making the polyamide resin in a state in which it is easy to separate from the silicone resin.
• a part or all of the polyamide resin may be separated from the silicone resin.
• the size of the polyamide resin airbag fabric to be subjected to heat treatment exceeds 10,000 cm 2 , it is preferable to cut it in advance to 10,000 cm 2 or less, preferably 2,500 cm 2 or less, using a known cutting machine or the like.
• the lower limit of the size of the airbag fabric to be subjected to heat treatment is not particularly limited, but for example, 0.01 cm 2 or more is preferable, and 0.1 cm 2 or more is more preferable.
• the shape of the airbag fabric fragments obtained by cutting is not particularly limited, and may be a quadrangular shape such as a rectangle or a square, a circular shape, an elliptical shape, or other polygonal shape, or an indefinite shape, and a quadrangular shape is preferable from the viewpoint of handling.
• the fragment shape is a quadrangular shape
• the length of one side is preferably within the range of 0.1 to 100 cm, and more preferably within the range of 0.2 to 50 cm.
• the treatment temperature in the heat treatment is 160°C or higher, preferably 165°C or higher, more preferably 170°C or higher, even more preferably 175°C or higher, and preferably 240°C or lower, more preferably 230°C or lower, even more preferably 220°C or lower, and even more preferably 210°C or lower.
• the treatment temperature in the heat treatment is preferably 165 to 240°C, more preferably 170 to 230°C, even more preferably 170 to 220°C, even more preferably 170 to 210°C, and even more preferably 175 to 210°C. If the treatment temperature is within the above range, the polyamide resin can be made to be in a state in which it is easy to separate from the silicone resin while suppressing deterioration such as decomposition of the polyamide resin.
• the treatment pressure in the heat treatment is equal to or higher than the saturated water vapor pressure at the treatment temperature, and is preferably 0.6 to 3.3 MPa, more preferably 0.7 MPa or higher, even more preferably 0.8 MPa or higher, even more preferably 0.9 MPa or higher, and more preferably 3.0 MPa or lower, even more preferably 2.8 MPa or lower, even more preferably 2.3 MPa or lower, and even more preferably 1.9 MPa or lower.
• the treatment pressure in the heat treatment is more preferably 0.7 to 3.0 MPa, even more preferably 0.8 to 3.0 MPa, even more preferably 0.9 to 3.0 MPa, even more preferably 0.9 to 2.8 MPa, even more preferably 0.9 to 2.3 MPa, and even more preferably 0.9 to 1.9 MPa. If the treatment pressure is within the above range, the polyamide resin can be made to be in a state in which it is easy to separate from the silicone resin while suppressing degradation such as decomposition of the polyamide resin.
• the state of H2O that is brought into contact with the airbag fabric may be gas (i.e., water vapor) or liquid (i.e., water). Specifically, it is saturated water vapor when heat treatment is performed at the saturated water vapor pressure at the treatment temperature, and it is subcritical water (also called compressed hot water or high-pressure hot water) when heat treatment is performed above the saturated water vapor pressure at the treatment temperature.
• gas i.e., water vapor
• liquid i.e., water
• subcritical water also called compressed hot water or high-pressure hot water
• Examples of methods for heat treatment include supplying high-pressure steam from a boiler or the like to a pressure-resistant reaction vessel containing the sample, or placing the sample and water in a pressure-resistant reaction vessel and heating it using a heater or the like.
• the airbag fabric is treated with high-temperature and high-pressure H2O , so that the polyamide resin can be made to be in a state in which it can be easily separated from the silicone resin while suppressing degradation such as decomposition of the polyamide resin.
• H2O high-temperature and high-pressure
• the processing time in the heat treatment may be set appropriately depending on the processing temperature and processing pressure, but is preferably 1 to 360 minutes, more preferably 3 minutes or more, even more preferably 5 minutes or more, even more preferably 10 minutes or more, more preferably 240 minutes or less, even more preferably 180 minutes or less, and even more preferably 120 minutes or less.
• the processing time in the heat treatment is more preferably 3 to 240 minutes, even more preferably 5 to 180 minutes, and even more preferably 10 to 120 minutes. If the processing time is within the above range, the polyamide resin can be made to be in a state in which it is easy to separate from the silicone resin while suppressing degradation such as decomposition of the polyamide resin.
• the temperature and/or pressure to the treatment temperature and/or treatment pressure in a short time.
• the reaction vessel and/or the airbag fabric may be cooled by natural cooling or may be cooled using a known cooling device.
• the heat treatment may be performed with stirring, if necessary, using a known stirring device such as a stirring blade.
• the stirring is preferably performed at a rotation speed of 10 to 3000 rpm, and more preferably at 20 to 2000 rpm.
• the polyamide resin can be made to be in a state in which it is easier to separate from the silicone resin.
• the heat treatment with stirring to generate friction between the fabrics, part or all of the polyamide resin that has been made to be in a state in which it is easier to separate by the heat treatment may be separated from the silicone resin.
• the heat treatment may be performed while retaining (fixing) the shape of at least one end of the airbag cloth, if necessary. Holding at least one end of the airbag cloth is preferable from the viewpoint of heat treatment efficiency, since it is possible to prevent the airbag cloth from folding or rolling up, resulting in the surface of the airbag cloth coated with the silicone resin not being exposed.
• a method for fixing at least one end of the airbag cloth for example, an end shape retaining member or frame made of metal may be provided at the end of the airbag cloth.
• the end shape retaining member is provided over a total of 50% or more of the entire length of the end of the airbag cloth, more preferably over a total of 70% or more, even more preferably over a total of 90% or more, and even more preferably over the entire length of the end.
• the airbag fabric may be subjected to post-treatment such as dehydration and drying.
• the dehydration and drying may be performed using a known dehydrator and/or dryer.
• a dryer such as an infrared heater, oven, or hot air dryer.
• Methods for recovering the polyamide resin include, for example, a method of separating and recovering the polyamide resin by applying an external force, such as by manually peeling the polyamide resin from the silicone resin.
• an external force such as by manually peeling the polyamide resin from the silicone resin.
• a method of visually separating and recovering the polyamide resin separated from the silicone resin can be used.
• the heat-treated airbag fabric When peeling off the polyamide resin by hand, the heat-treated airbag fabric may be further subjected to external force such as kneading or rubbing before being peeled off, but from the standpoint of ease of separation of the polyamide resin, it is preferable to be able to peel it off by hand without applying further external force such as kneading or rubbing.
• the polyamide resin in the heat-treated airbag fabric is easily separated from the silicone resin, when external forces such as frictional forces and shear forces are applied due to stirring or crushing, the polyamide resin easily separates. For this reason, the airbag fabric after heat treatment may be stirred and/or crushed to separate the polyamide resin from the silicone resin, and then the polyamide resin from which the silicone resin has been removed may be recovered by visually separating them.
• the heat-treated sample is pulverized to separate the polyamide resin
• the recovered polyamide resin may be washed with a cleaning solution such as water or an organic solvent, or may be dried or otherwise processed as appropriate.
• the polyamide resin recovered by the recycling method of the present invention does not substantially contain silicone resin.
• substantially does not contain means that the content of silicone resin in the recycled polyamide resin is 1 mass% or less, more preferably 0.5 mass% or less, and even more preferably 0.1 mass% or less.
• the content of silicone resin in the recycled polyamide resin is preferably 0 to 1 mass%, more preferably 0 to 0.5 mass%, and even more preferably 0 to 0.1 mass%.
• Recycled polyamide resin that does not substantially contain silicone resin has high recyclability.
• the content (residual amount) of silicone resin contained in the recycled polyamide resin can be calculated based on the obtained value by, for example, determining the mass of silicone resin in the recycled polyamide resin using a Fourier transform infrared spectrophotometer (FT-IR). Furthermore, when recycled polyamide resin is analyzed using the above analytical equipment, if no characteristic peaks due to silicone resin are detected, the recycled polyamide resin can be considered to be one from which silicone resin has been completely removed.
• FT-IR Fourier transform infrared spectrophotometer
• polyamide resin from which the silicone resin has been removed is obtained by contacting the polyamide resin with high-temperature, high-pressure H2O , so that alkali treatment is not necessary, deterioration of the polyamide resin and silicone resin due to alkali treatment can be avoided, and complicated operations such as removing the alkaline aqueous solution and post-treatment of the waste liquid are not required, making it possible to recycle the airbag fabric easily.
• the polyamide resin recovered by the airbag fabric recycling method of the present invention has suppressed changes in physical properties such as molecular weight compared to the polyamide resin in the base fabric before treatment. If changes in the physical properties of the polyamide resin are suppressed, it can be reused without further treatment such as polymerization, and therefore has high recyclability.
• the use of the recovered polyamide resin is not particularly limited, and it can be reused, for example, by decomposing it down to the monomers and repolymerizing it (chemical recycling), but from the standpoint of energy costs, it is preferable to reuse it by melting it and re-pelletizing it without decomposing it down to the monomers (material recycling).
• the degree of deterioration of polyamide resin can be confirmed by the relative viscosity of the polyamide resin. Since the relative viscosity is proportional to the molecular weight of the resin, the higher the relative viscosity, the higher the molecular weight of the recovered polyamide resin, that is, the more the polymer state is maintained. Specifically, if the relative viscosity is 1.3 or more (preferably 1.5 or more, more preferably 1.7 or more, even more preferably 1.9 or more, even more preferably 2.1 or more, and even more preferably 2.3 or more), it can be said that the polyamide resin is suitable for material recycling.
• the relative viscosity (RV) of the polyamide resin can be calculated by dissolving 0.25 g of polyamide resin in 46 g of 96% sulfuric acid, putting 10 ml of this solution into an Oswald viscosity tube, measuring at 20°C, and calculating it from the following formula.
• RV T/T0 (RV: relative viscosity, T: drop time of sample solution, T0: drop time of solvent)
• RV0 relative viscosity
• the ratio of RV (relative viscosity of the recovered polyamide resin) to RV0 (RV/RV0) is 0.4 or more (preferably 0.5 or more, more preferably 0.6 or more, even more preferably 0.7 or more, and even more preferably 0.8 or more). If the value of RV/RV0 is within the above range, the polyamide resin obtained by the recovery method of the present invention is inhibited from deteriorating, and can be said to be a polyamide resin that can be suitably used for material recycling.
• the airbag fabric to be used in the recycling method of the present invention is a polyamide resin airbag fabric having a base fabric made of polyamide resin and at least one side of the base fabric coated with a silicone resin.
• Examples of the polyamide resin airbag fabric include waste materials generated during the manufacture of airbags and waste materials such as used airbags.
• the polyamide resin that constitutes the base fabric is a polymer that has an amide bond in the main chain.
• polyamide resins include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polylauryl lactam (nylon 12), polyundecane amide (nylon 11), and copolymers and mixtures thereof.
• polycaproamide resin obtained by polycondensation of ⁇ -caprolactam commonly known as nylon 6, and nylon 66 are preferably used in terms of heat resistance and cost.
• nylon 6 and nylon 66 are preferred in terms of versatility when recycling.
• the base fabric is preferably a woven fabric made of multifilament polyamide fibers.
• Examples of the woven fabric include plain weave, twill weave, satin weave, and variations of these weaves.
• the number of filaments in the multifilament yarn constituting the woven fabric (base fabric) is preferably, for example, 30 to 200, and more preferably 40 to 180.
• the number of filaments can be determined by counting from a cross-sectional photograph of the multifilament yarn.
• the total fineness of the multifilament yarns constituting the woven fabric (base fabric) is preferably, for example, 200 to 1000 dtex, and more preferably 250 to 800 dtex, from the viewpoint of obtaining recycled polyamide resin with higher recyclability.
• the total fineness of the multifilament yarns can be measured in accordance with JIS L1013 (2010) 8.3.1.
• the tensile strength of the multifilament yarn that constitutes the woven fabric (base fabric) is preferably, for example, 6.0 to 10 cN/dtex, and more preferably 6.5 to 9.5 cN/dtex, from the viewpoint of obtaining a recycled polyamide resin with higher recyclability.
• the tensile strength of the multifilament yarn can be measured in accordance with JIS L1013 (2010) 8.5.1.
• the weave density of the woven fabric (base fabric) is preferably, for example, 35 to 80 threads/2.54 cm in both the warp and weft directions, and more preferably 40 to 75 threads/2.54 cm.
• the weave density can be measured in accordance with JIS L1096 (2010) 8.6.1.
• the cover factor (CF) of the woven fabric (base fabric) is, for example, preferably 1,500 to 2,500, and more preferably 1,700 to 2,300.
• the base fabric may contain additives other than polyamide resin.
• additives include antioxidants, heat stabilizers, smoothing agents, antistatic agents, thickeners, flame retardants, weather resistance agents, coloring inhibitors, colorants, etc.
• a coating resin containing silicone resin is applied to at least one side of the base fabric, forming a silicone resin layer.
• the silicone resin is not particularly limited, but specific examples include addition polymerization type silicone rubber. Examples include dimethyl silicone rubber, methyl vinyl silicone rubber, methyl phenyl silicone rubber, trimethyl silicone rubber, fluoro silicone rubber, methyl silicone resin, methyl phenyl silicone resin, methyl vinyl silicone resin, epoxy modified silicone resin, acrylic modified silicone resin, polyester modified silicone resin, etc. Among these, addition polymerization type methyl vinyl silicone rubber is preferred.
• the viscosity of the coating resin is preferably 5,000 to 40,000 mPa ⁇ sec, and more preferably 7,000 to 38,000 mPa ⁇ sec. As long as the viscosity is within the above range, the coating resin may be either solvent-based or solventless, but solventless resins are preferred. In this specification, the viscosity of the resin composition containing additives other than the resin, i.e., the viscosity of the resin that is actually applied to the base fabric, is referred to as the "resin viscosity.”
• the coating resin may contain additives other than silicone resin and solvent.
• the additives include, for example, reactive curing agents such as platinum catalysts (specifically, platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid with olefins, aldehydes, vinylsiloxanes or acetylene alcohols, etc.); adhesion aids such as amino-based silane coupling agents, epoxy-modified silane coupling agents, vinyl-based silane coupling agents, chlorine-based silane coupling agents, and mercapto-based silane coupling agents; reinforcing inorganic fillers such as fumed silica and dry silica; non-reinforcing inorganic fillers such as crosslinkable silicones (silicone resins) with adjusted end groups, calcium carbonate, calcium silicate, and titanium dioxide; antioxidants; antistatic agents; flame retardants; weather resistance agents; coloring inhibitors; colorants; etc.
• reactive curing agents such as
• the content is preferably 100 to 2000 ppm, and more preferably 150 to 1800 ppm, in terms of the amount of platinum metal per 100 parts by mass of silicone resin.
• a silane coupling agent is contained as an adhesion promoter
• the content thereof is preferably 0.01 to 3 parts by mass, and more preferably 0.02 to 2 parts by mass, per 100 parts by mass of the silicone resin.
• an inorganic filler is contained, the content thereof is preferably 0.1 to 200 parts by mass, and more preferably 0.1 to 100 parts by mass, per 100 parts by mass of the silicone resin.
• the coating resin (i.e., silicone resin) on the base fabric may be applied using a conventional, well-known application method.
• application methods include knife coating, roll coating, reverse coating, gravure coating, gravure reverse coating, kiss coating, etc., and it is preferable that the silicone resin is applied by knife coating.
• the amount of silicone resin applied to the polyamide resin airbag fabric is preferably 5 to 150 g/ m2 , more preferably 7 g/ m2 or more, even more preferably 10 g/ m2 or more, and more preferably 120 g/ m2 or less, even more preferably 100 g/ m2 or less, and even more preferably 70 g/ m2 or less. That is, the amount of silicone resin applied to the polyamide resin airbag fabric is more preferably 7 to 120 g/ m2 , more preferably 10 to 100 g/ m2 , and even more preferably 10 to 70 g/ m2 .
• the polyamide resin recovered by the recycling method of the present invention can be used for chemical recycling or material recycling to form recycled products that contain the polyamide resin as at least a part of the raw material.
• recycled products include recycled polyamide resin compositions and airbag base fabrics.
• Polyamide resin airbag fabric 1 A plain woven fabric was obtained using a polyamide 66 multifilament yarn with a raw yarn strength of 8.4 cN/dtex, a total fineness of 470 dtex, and 68 filaments, with a warp density of 46/2.54 cm, a weft density of 46/2.54 cm, and a cover factor of 1,994.
• An addition polymerization type solventless vinyl methyl silicone resin with a resin viscosity of 14,000 mPa ⁇ sec was applied to one side of the woven fabric (base fabric) and dried at 200°C for 1 minute to obtain a polyamide resin airbag fabric 1 with a resin application amount of 25 g/ m2 .
• the weight ratio of polyamide resin in the polyamide resin airbag fabric 1 was 87%.
• Example 1 The polyamide resin airbag fabric 1 was cut into 50 cm squares. The cut samples were placed in a high-pressure reactor, and steam was added to the reactor to bring the pressure to 1.6 MPa and 200° C., and pressure treatment (heat treatment) was performed for 30 minutes while stirring. The treated samples were evaluated for ease of separation, and the peel test evaluation result was "Excellent," and the polyamide resin from which the silicone resin had been removed could be recovered.
• Example 2 The treatment was carried out in the same manner as in Example 1, except that the heat treatment conditions were 1.0 MPa, 180° C., and 60 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Good”, and the polyamide resin from which the silicone resin had been removed could be recovered.
• Example 3 The treatment was carried out in the same manner as in Example 1, except that the heat treatment conditions were 1.7 MPa, 205° C., and 60 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Excellent”, and the polyamide resin from which the silicone resin had been removed could be recovered.
• Example 4 The treatment was carried out in the same manner as in Example 1, except that the heat treatment conditions were 1.3 MPa, 190° C., and 60 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Excellent”, and the polyamide resin from which the silicone resin had been removed could be recovered.
• Example 5 The polyamide resin airbag fabric 1 was cut into 15 cm squares, and a metal frame was provided around the periphery of the sample using aluminum foil to maintain the overall shape of the end of the sample.
• the metal-framed sample and water were placed in a high-pressure reactor and heat-treated at 210°C and 2.0 MPa for 10 minutes.
• the treated sample was evaluated for ease of separation, and the peel test evaluation result was "Excellent", and the polyamide resin from which the silicone resin had been removed could be recovered.
• the recovery rate of the polyamide resin was 72%, and the relative viscosity of the recovered polyamide resin was 2.40.
• Example 6 The treatment was carried out in the same manner as in Example 5, except that the heat treatment conditions were 210°C, 2.0 MPa, and 5 minutes. The treated sample was evaluated for ease of separation, and the peel test evaluation result was "Excellent", and the polyamide resin from which the silicone resin had been removed could be recovered. The recovery rate of the polyamide resin was 43%, and the relative viscosity of the recovered polyamide resin was 2.47.
• Example 7 The treatment was carried out in the same manner as in Example 5, except that the heat treatment conditions were 220°C, 2.2 MPa, and 5 minutes. The treated sample was evaluated for ease of separation, and the peel test evaluation result was "Excellent", and the polyamide resin from which the silicone resin had been removed could be recovered. The recovery rate of the polyamide resin was 95%, and the relative viscosity of the recovered polyamide resin was 2.29.
• Example 8 The treatment was carried out in the same manner as in Example 5, except that the heat treatment conditions were 200°C, 1.6 MPa, and 30 minutes. The treated sample was evaluated for ease of separation, and the peel test evaluation result was "Excellent", and the polyamide resin from which the silicone resin had been removed could be recovered. The recovery rate of the polyamide resin was 85%, and the relative viscosity of the recovered polyamide resin was 2.38.
• Example 9 The treatment was carried out in the same manner as in Example 5, except that the heat treatment conditions were 200°C, 1.6 MPa, and 5 minutes. The treated sample was evaluated for ease of separation, and the peel test evaluation result was "Excellent", and the polyamide resin from which the silicone resin had been removed could be recovered. The recovery rate of the polyamide resin was 18%, and the relative viscosity of the recovered polyamide resin was 2.65.
• Example 1 The treatment was carried out in the same manner as in Example 1, except that the heat treatment conditions were 0.48 MPa, 150° C., and 30 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Poor”, and the polyamide resin from which the silicone resin had been removed could not be recovered.
• Example 2 The treatment was carried out in the same manner as in Example 1, except that the heat treatment conditions were 0.48 MPa, 150° C., and 60 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Poor”, and the polyamide resin from which the silicone resin had been removed could not be recovered.
• Comparative Example 4 The treatment was carried out in the same manner as in Comparative Example 3, except that the heat treatment conditions were 210° C. and 60 minutes. When the treated sample was evaluated for ease of separation, the evaluation result of the peel test was “Poor”, and the polyamide resin from which the silicone resin had been removed could not be recovered.

Landscapes

• Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Mechanical Engineering (AREA)
• Air Bags (AREA)
• Treatment Of Fiber Materials (AREA)
• Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=91588472

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (7)

• 2023
  • 2023-10-26 WO PCT/JP2023/038666 patent/WO2024135089A1/ja not_active Ceased
  • 2023-10-26 JP JP2024565633A patent/JPWO2024135089A1/ja active Pending
  • 2023-10-26 CN CN202380080031.XA patent/CN120225329A/zh active Pending
  • 2023-10-26 EP EP23906463.7A patent/EP4640394A1/en active Pending

Patent Citations (7)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events