Heat-insulating and sound-absorbing light foaming material and preparation method thereof

Abstract

The invention discloses a heat-insulating and sound-absorbing lightweight foam material and a preparation method thereof. Comprising the following components by weight: polyolefin resin and / or a polyolefin copolymer, a foaming agent, a flame retardant, a foaming aid, a filler, a color master batch, and / or a thermoplastic elastomer, and / or rubber. The prepared foaming material is prepared through the steps of raw material mixing, mixing granulation, master slice extrusion, irradiation crosslinking, foaming and the like. Compared with the prior art, the heat-insulating and sound-absorbing lightweight foam material prepared by the invention has the advantage of excellent mechanical properties.

Description

Technical Field

[0001] The present invention relates to the technical field of foamed materials, and particularly to a lightweight foamed material with heat insulation and sound absorption functions and a preparation method thereof. Background Art

[0002] With the development of the domestic economy, the rapid development of automobiles, high-speed rails, and large-scale industries has generated a large amount of noise, which has brought serious troubles to people's lives.

[0003] Crosslinked polyolefin foamed materials are widely used in fields such as construction, automobiles, and high-speed rails due to their excellent characteristics such as light weight, heat insulation, heat preservation, corrosion resistance, and sound absorption. According to their structures, they can be classified into closed-cell and open-cell foamed materials. Among them, the closed-cell polyolefin foamed materials have independent internal cells, reduced heat convection, and excellent heat insulation performance, making them good heat-insulating and heat-preserving materials. For this kind of polyolefin closed-cell foamed materials, the technology is mature and the process is simple, but there are problems such as poor sound absorption performance, difficult creep recovery, and poor flame retardant performance. The open-cell polyolefin foamed materials have interconnected cells, which can effectively absorb sound waves, cause the sound waves to continuously reflect inside them, and convert the sound energy into heat energy, thus achieving a noise reduction effect. However, for this kind of polyolefin foamed material, the flame retardant performance is poor, which greatly limits its application in fields such as high-speed rails, large shopping malls, and automobiles. In view of this, it is urgent to develop a polyolefin foamed material with both sound absorption and flame retardant properties to meet the needs of related industries. CN113943489A discloses a soft foam polymer material, including: block copolymer 10 - 90%, thermoplastic polyurethane elastomer 4 - 84%, polyurethane ionomer 1 - 25%, and foaming nucleating agent 0.1 - 5%. The foamed material composition uses a blend of three types of polymers, namely block copolymer, thermoplastic polyurethane elastomer, and polyurethane ionomer, and is combined with a foaming nucleating agent, so that the obtained foamed material has the characteristics of light weight, high resilience, and low compression set; at the same time, the foamed material has excellent comprehensive mechanical properties such as tear resistance and tensile properties. However, the sound insulation effect of the soft foam polymer material prepared by this method is not very ideal.

[0004] CN104003606B discloses a high-temperature manufacturing method of an inorganic foamed material and the inorganic foamed material thus prepared. The preparation method is to mix thin-film transistor liquid crystal display glass, soda-lime glass, and a foaming agent, and sequentially preform, heat to an appropriate temperature for sintering, and anneal to make a lightweight inorganic foamed material, and the foamed material has low water absorption, heat insulation, sound insulation, and fire prevention effects. However, due to the internal pore structure of the foamed material, its heat insulation effect may be affected. Summary of the Invention

[0005] In view of the above defects of the prior art, the technical problem to be solved by the present invention is to provide a lightweight foaming material with heat insulation and sound absorption functions. This foaming material has the functions of flame retardancy, heat insulation and sound absorption, and has good tensile strength, which helps to enhance the durability and stability of the lightweight foaming material.

[0006] To achieve the above object, the present invention provides a lightweight foaming material with heat insulation and sound absorption functions. Calculated by weight parts, it includes the following weight components: 40-120 parts of polyolefin resin, and / or 10-60 parts of polyolefin copolymer, 1-40 parts of foaming agent, 1-20 parts of flame retardant, 1-20 parts of foaming aid, 1-20 parts of filler, 1-5 parts of masterbatch, and / or 1-30 parts of thermoplastic elastomer, and / or 1-30 parts of rubber.

[0007] Preferably, the polyolefin resin is at least one of low-density polyethylene, high-density polyethylene, and polypropylene; the polyolefin copolymer is ethylene-vinyl acetate copolymer.

[0008] More preferably, the polyolefin resin can also be modified polypropylene.

[0009] Preferably, the preparation method of the modified polypropylene includes the following steps, calculated by weight parts: A1. Dry 40-100 parts of polypropylene and the modifier in an oven at 60-80°C for 10-20 minutes respectively. Then add 0.1-1 part of diisopropylbenzene peroxide, 1-5 parts of modifier, and 0.1-3 parts of hydroxyapatite to the polypropylene and mix at 200-300 rpm for 20-40 minutes to obtain a mixture. Then add the mixture, 1-4 parts of grafting agent, and 1-6 parts of styrene to an internal mixer and melt-blend at 190-220°C at 50-100 rpm for 5-10 minutes to obtain a molten mixture; A2. Add the molten mixture in A1 to 180-250 parts of xylene solution, stir at 140-160°C at 200-250 rpm for 1-2 hours, then add it to 150-250 parts of acetone for sedimentation to remove ungrafted small molecules. After suction filtration, dry it in an oven at 80-100°C for 10 minutes to obtain modified polypropylene.

[0010] Preferably, the modifier is any one of ellagic acid, quercetin, and trans-1-(3-carboxy-4-hydroxyphenyl)-2-(2,5-dihydroxyphenyl)ethylene.

[0011] Preferably, the grafting agent is any one of poly(tert-butyl methacrylate-co-glycidyl methacrylate) and acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer.

[0012] Preferably, the blowing agent is any one of azodicarbonamide, azodiisobutyronitrile, and barium azodicarboxylate; the blowing aid is a mixture of zinc oxide and zinc stearate, and the mass ratio of zinc oxide to zinc stearate is 99:1.

[0013] Preferably, the flame retardant is one or a mixture of trichloroethyl phosphate, trichloropropyl phosphate, expanded graphite, aluminum hydroxide, and magnesium hydroxide.

[0014] Preferably, the filler is any one or a mixture of two of nano calcium carbonate with a particle size of 0.01 - 0.1 μm and ultrafine talc powder with a particle size of 0.1 - 10 μm.

[0015] Preferably, the thermoplastic elastomer is one or a mixture of two of diene - based thermoplastic elastomers or metallocene - catalyzed polyolefin - based thermoplastic elastomers.

[0016] Preferably, the rubber is any one or a mixture of ethylene - propylene rubber, nitrile rubber, styrene - butadiene rubber, and silicone rubber.

[0017] Preferably, the melt index of the low - density polyethylene is 0.5 - 4.0 g / 10min, the melt index of the high - density polyethylene is 0.5 - 6.0 g / 10min, the melt index of the polypropylene is 2 - 15 g / 10min; the melt index of the ethylene - vinyl acetate copolymer is 0.5 - 8 g / 10min.

[0018] More preferably, the diene - based thermoplastic elastomer is a mixture of 1,4 - trans - polyisoprene rubber and 1,1,4,4 - tolyl - 1,3 - butadiene.

[0019] The present invention also provides a preparation method of a flame - retardant and sound - absorbing polyolefin foaming material, which includes the following steps: S1. Weigh 40 - 120 parts of polyolefin resin, and / or 10 - 60 parts of polyolefin copolymer, 1 - 30 parts of thermoplastic elastomer, 1 - 30 parts of rubber, 1 - 40 parts of blowing agent, 1 - 20 parts of flame retardant, 1 - 20 parts of blowing aid, 1 - 20 parts of filler, and 1 - 5 parts of masterbatch to obtain a mixed raw material; S2. Kneading and pelletizing: Pour the mixed raw material prepared in S1 into an internal mixer for mixing and pelletizing to obtain masterbatch; S3. Extruding mother sheet: Pre - mix and dry the masterbatch prepared in S2, and then send it into a single - screw extruder to extrude into a sheet and wind it to obtain a mother roll; S4. Irradiation cross - linking: Perform electron irradiation cross - linking with an energy of 30 KeV - 100 KeV on the mother roll obtained in S3 to obtain a cross - linked mother roll; S5. Foaming: Carry out temperature - rising foaming, trimming, and winding on the cross - linked mother roll obtained in S4 in a horizontal foaming furnace to obtain an open - cell sound - absorbing polyolefin foaming material.

[0020] In this formulation, each raw material and its function are as follows: Advantages of the present invention: Flame retardants are functional additives that impart flame retardancy to flammable polymers. They mainly play their flame retardant role through various mechanisms, such as endothermic, covering, inhibiting chain reactions, etc. Under high-temperature conditions, flame retardants can absorb part of the heat released by combustion, reduce the surface temperature of combustibles, effectively inhibit the generation of flammable gases, and prevent the spread of combustion. At the same time, flame retardants can form a glassy or stable foam covering layer in combustible materials, isolating oxygen, and having the functions of heat insulation, oxygen isolation, and preventing the outward escape of combustible gases.

[0021] Masterbatch mainly plays the role of providing color for polymers in polyolefin foamed materials. By adding an appropriate amount of masterbatch, the foamed material can obtain the desired color effect, thereby realizing the appearance customization of the product. In addition, the masterbatch should also have good dispersibility to ensure that it can be evenly dispersed inside the material during the polymer processing process, avoiding problems such as color difference or color spots.

[0022] The modifier contains multiple phenolic hydroxyl functional groups. Similar to the structure of phenol, it has a strong hydrogen-donating ability and is expected to play the role of quenching free radicals in the same way. And the electron-rich structure of tea polyphenols is also expected to play the role of stabilizing the tertiary carbon free radicals of polypropylene, inhibiting degradation during the grafting process, thereby improving the mechanical properties of modified polypropylene, and further improving the mechanical properties of lightweight foamed materials.

[0023] Styrene is usually added during the melt grafting process of polypropylene to increase the grafting rate of graft monomers and inhibit degradation during the grafting process. Compared with graft monomers, the electron cloud of styrene monomer is more abundant. Therefore, when styrene is added to the grafting system, styrene monomer will preferentially graft onto the macromolecular free radicals of polypropylene, and the π-electron conjugate structure in styrene can play the role of stabilizing the macromolecular free radicals of polypropylene, thereby reducing β-chain scission reactions and inhibiting degradation during the grafting process. At the same time, the abundant electron cloud in styrene makes the graft monomers easier to graft onto the polypropylene styrene free radicals, increasing the grafting rate of graft monomers on polypropylene.

[0024] Hydroxyapatite has excellent flame retardant properties. Under high-temperature conditions, the material added with hydroxyapatite can decompose rapidly and produce molten liquid, and a large amount of non-toxic gases, such as water and carbon dioxide, etc., will be released during this process. At the same time, because hydroxyapatite contains hydroxyl functional groups that can react with the carboxyl functional groups contained in the modifier, the solubility of hydroxyapatite is further increased. And as a filler, the increased solubility of hydroxyapatite increases the mechanical properties of modified polypropylene.

[0025] The grafting agent contains epoxy functional groups, which can undergo chemical reactions with various functional groups, and the monomer has a relatively high boiling point, which is close to the temperature during the melt grafting reaction. The epoxy functional groups contained in the grafting agent can react with the phenolic hydroxyl groups in the modifier, and then link the modifier to the polypropylene chain segment.

[0026] 1. Compared with the prior art, the flame-retardant sound-absorbing foamed material of the present invention has excellent properties such as light weight, environmental protection, and corrosion resistance, can be mass-produced, aims to meet the market demand, and has a broad market prospect.

[0027] 2. Compared with the prior art, the modified polypropylene is prepared by reacting the epoxy functional groups in the grafting agent with the phenolic hydroxyl functional groups in the modifier to link the modifier to the polypropylene chain segment. The modified polypropylene and other raw materials are used to prepare a lightweight foamed material by melting, and its tensile strength is better. Specific Embodiments

[0028] Use the parameters and sources of specific chemical substances.

[0029] Polypropylene with a melt index of 12 g / 10 min, grade: INEOS PP 101-XA12, Suzhou Shaoxiang Plastic Import and Export Co., Ltd.

[0030] Polyethylene with a melt index of 0.9 g / 10 min, product number: M2710EP, Dongguan Yili Plastic Co., Ltd.

[0031] Polyethylene with a melt index of 3 g / 10 min, grade: 18-3, Beijing Zhonglai Chemical Co., Ltd.

[0032] Ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, model: EV560, Dongguan Yisheng Plastic Co., Ltd.

[0033] Ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, model: 14-2, Dongguan Qunfa Plastics Co., Ltd.

[0034] Ethylene-propylene rubber: model: J-3092E, Dongguan Canhui New Material Technology Co., Ltd.

[0035] Metallocene-catalyzed olefinic thermoplastic elastomer: grade: POE8450, Shanghai Oshuo Plastics Co., Ltd.

[0036] Black masterbatch: grade: PA8087, Shaoguan Derui Chemical Industry Co., Ltd.

[0037] Nano calcium carbonate, particle size 0.1 μm.

[0038] Trans-1-(3-carboxy-4-hydroxyphenyl)-2-(2,5-dihydroxyphenyl)ethene, CAS No.: 150258-63-2.

[0039] Poly(tert-butyl methacrylate-co-glycidyl methacrylate), CAS No.: 70939-77-4.

[0040] Acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer, CAS No.: 64255-97-6.

[0041] Hydroxyapatite, 20 mesh.

[0042] Example 1 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Put 50 kg of polyethylene with a melt index of 0.9 g / 10 min, 30 kg of polypropylene with a melt index of 12 g / 10 min, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, 15 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 120 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S3. Carry out 80 KeV electron irradiation on the mother roll prepared in S2 for 20 min for crosslinking; S4. Carry out horizontal furnace foaming on the crosslinked mother roll prepared in S3 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0043] Example 2 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Put 80 kg of polyethylene with a melt index of 0.9 g / 10 min, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, 10 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide, 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide, 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain the foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 80 °C, zone 2 at 90 °C, zone 3 at 100 °C, zone 4 at 110 °C, zone 5 at 115 °C, zone 6 at 120 °C, and the die temperature is 120 °C. Finally, wind it up to obtain the mother roll; S3. Crosslink the mother roll prepared in S2 by electron irradiation at 100 KeV for 20 min; S4. Carry out horizontal furnace foaming on the crosslinked mother roll in S3, and the foaming temperature is 240 °C, to obtain the heat-insulating and sound-absorbing lightweight foamed material.

[0044] Example 3 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Put 70 kg of polyethylene with a melt index of 3 g / 10 min, 30 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 15 kg of ethylene-propylene rubber, 12 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide, 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide, 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain the foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 30 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 80 °C, zone 2 at 90 °C, zone 3 at 100 °C, zone 4 at 110 °C, zone 5 at 115 °C, zone 6 at 120 °C, and the die temperature is 120 °C. Finally, wind it up to obtain the mother roll; S3. Crosslink the mother roll prepared in S2 by electron irradiation at 75 KeV for 20 min; S4. Carry out horizontal furnace foaming on the crosslinked mother roll in S3, and the foaming temperature is 240 °C, to obtain the heat-insulating and sound-absorbing lightweight foamed material.

[0045] Example 4 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Put 70 kg of polyethylene with a melt index of 3 g / 10 min, 30 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 13 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 30 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 80 °C, zone 2 at 90 °C, zone 3 at 100 °C, zone 4 at 110 °C, zone 5 at 115 °C, zone 6 at 120 °C, and the die temperature is 120 °C. Finally, wind it up to obtain a mother roll; S3. Crosslink the mother roll prepared in S2 by 80 KeV electron irradiation for 20 min; S4. Foam the crosslinked mother roll prepared in S3 horizontally in a furnace at a foaming temperature of 240 °C, to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0046] Example 5 A preparation method of a lightweight foamed material with heat insulation and sound absorption properties, comprising the following steps: S1. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of polypropylene with a melt index of 12 g / 10 min, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 10 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S3. Crosslink the mother roll prepared in S2 by 90 KeV electron irradiation for 20 min; S4. Foam the mother roll crosslinked in S3 in a horizontal furnace at a foaming temperature of 250 °C to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0047] Example 6 A method for preparing a lightweight foamed material with heat insulation and sound absorption properties, comprising the following steps: S1. Put 50 kg of polyethylene with a melt index of 3 g / 10 min, 50 kg of polypropylene with a melt index of 12 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azobisisobutyronitrile, 21.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Premix the foaming masterbatch prepared in S1, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a high-speed mixer at 70 °C for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S3. Crosslink the mother roll prepared in S2 by electron irradiation at 100 KeV for 20 min; S4. Foam the mother roll crosslinked in S3 in a horizontal furnace at a foaming temperature of 250 °C to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0048] Example 7 A method for preparing a lightweight foamed material with heat insulation and sound absorption properties, comprising the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and a modifier in an 80 °C oven for 10 min, then add 0.3 kg of dicumyl peroxide, 3 kg of modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of grafting agent, and 1 kg of styrene into an internal mixer and melt-blend at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 to 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it to 150 L of acetone for sedimentation to remove ungrafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain modified polypropylene.

[0049] S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azodiisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, and 1 kg of nano calcium carbonate, 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S4. Pre-mix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a high-speed mixer at 70 °C for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S5. Carry out 100 KeV electron irradiation on the mother roll obtained in S4 for 20 min for cross-linking; S6. Carry out horizontal furnace foaming on the cross-linked mother roll obtained in S5 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0050] Among them, the modifier is trans-1-(3-carboxy-4-hydroxyphenyl)-2-(2,5-dihydroxyphenyl)ethylene.

[0051] The grafting agent is acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer.

[0052] Example 8 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and the modifier in an 80 °C oven for 10 min respectively. Then add 0.3 kg of diisopropyl peroxide, 3 kg of the modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of the grafting agent, and 1 kg of styrene into an internal mixer and melt-blend at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 into 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it into 150 L of acetone for sedimentation to remove un-grafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain modified polypropylene; S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain the foaming masterbatch; S4. Premix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain the mother roll; S5. Carry out 100 KeV electron irradiation on the mother roll prepared in S4 for 20 min for crosslinking; S6. Carry out horizontal furnace foaming on the crosslinked mother roll in S5 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0053] Among them, the modifier is ellagic acid.

[0054] The grafting agent is acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer.

[0055] Example 9 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and the modifier in an 80 °C oven for 10 min respectively, then add 0.3 kg of diisopropyl peroxide, 3 kg of the modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of the grafting agent, and 1 kg of styrene into an internal mixer and carry out melt blending at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 into 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it into 150 L of acetone for sedimentation to remove the ungrafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain the modified polypropylene; S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S4. Pre-mix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a high-speed mixer at 70 °C for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S5. Carry out 100 KeV electron irradiation on the mother roll prepared in S4 for 20 min for crosslinking; S6. Carry out horizontal furnace foaming on the crosslinked mother roll in S5 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0056] Among them, the modifier is quercetin.

[0057] The grafting agent is acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer.

[0058] Example 10 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material, comprising the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and the modifier in an 80 °C oven for 10 min respectively, then add 0.3 kg of diisopropyl peroxide, 3 kg of the modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of the grafting agent, and 1 kg of styrene into an internal mixer and carry out melt blending at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 into 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it into 150 L of acetone for sedimentation to remove un-grafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain modified polypropylene; S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azodiisobutyronitrile, a mixture of 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of a compound of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S4. Pre-mix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S5. Subject the mother roll prepared in S4 to 100 KeV electron irradiation for 20 min for crosslinking; S6. Foam the mother roll crosslinked in S5 in a horizontal furnace at a foaming temperature of 250 °C to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0059] Among them, the modifier is trans-1-(3-carboxy-4-hydroxyphenyl)-2-(2,5-dihydroxyphenyl)ethylene.

[0060] The grafting agent is poly(tert-butyl methacrylate-co-glycidyl methacrylate).

[0061] Comparative Example 1 A preparation method of a lightweight foamed material with heat insulation and sound absorption properties includes the following steps: S1. Put 100 kg of polyethylene with a melt index of 0.9 g / 10 min, 15 kg of azodiisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 120 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S3. Subject the mother roll prepared in S2 to 80 KeV electron irradiation for 20 min for crosslinking; S4. Horizontally foam the mother roll crosslinked in S3 at a foaming temperature of 250 °C to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0062] Comparative Example 2 A method for preparing a lightweight foamed material with heat insulation and sound absorption properties, comprising the following steps: S1. Put 80 kg of polyethylene with a melt index of 0.9 g / 10 min, 10 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide, 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide, 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S2. Pre-mix the foaming masterbatch prepared in S1, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 3.5 g / 10 min, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 80 °C, zone 2 at 90 °C, zone 3 at 100 °C, zone 4 at 110 °C, zone 5 at 115 °C, zone 6 at 120 °C, and the die temperature is 120 °C. Finally, wind it up to obtain a mother roll; S3. Subject the mother roll prepared in S2 to 100 KeV electron irradiation for 20 min for crosslinking; S4. Horizontally foam the mother roll crosslinked in S3 at a foaming temperature of 240 °C to obtain a lightweight foamed material with heat insulation and sound absorption properties.

[0063] Comparative Example 3 A method for preparing a lightweight foamed material with heat insulation and sound absorption properties, comprising the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and the modifier in an 80 °C oven for 10 min respectively. Then add 0.3 kg of dicumyl peroxide, 3 kg of modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of grafting agent, and 1 kg of styrene to an internal mixer and melt-blend at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 to 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it to 150 L of acetone for sedimentation to remove ungrafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain modified polypropylene.

[0064] S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain a foaming masterbatch; S4. Pre-mix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefinic thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge it into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind it up to obtain a mother roll; S5. Carry out 100 KeV electron irradiation on the mother roll prepared in S4 for 20 min for cross-linking; S6. Carry out horizontal furnace foaming on the cross-linked mother roll in S5 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0065] Among them, the modifier is tea polyphenol.

[0066] The grafting agent is acrylonitrile-butadiene-divinylbenzene-glycidyl methacrylate copolymer.

[0067] Comparative Example 4 A preparation method of a heat-insulating and sound-absorbing lightweight foamed material includes the following steps: S1. Dry 40 kg of polypropylene with a melt index of 12 g / 10 min and the modifier in an 80 °C oven for 10 min respectively. Then add 0.3 kg of dicumyl peroxide, 3 kg of the modifier, and 0.3 kg of hydroxyapatite to the polypropylene and mix at 200 rpm for 20 min to obtain a mixture. Then add the mixture, 2 kg of the grafting agent, and 1 kg of styrene into an internal mixer and carry out melt blending at 190 °C and 50 rpm for 5 min to obtain a molten mixture; S2. Add the molten mixture in S1 into 180 L of xylene solution, stir at 140 °C and 200 rpm for 1 h, then add it into 150 L of acetone for sedimentation to remove un-grafted small molecules. After suction filtration, dry it in an 80 °C oven for 10 min to obtain the modified polypropylene; S3. Put 40 kg of polyethylene with a melt index of 3 g / 10 min, 40 kg of the above-mentioned modified polypropylene, 20 kg of ethylene-vinyl acetate copolymer with a melt index of 2 g / 10 min, 10 kg of metallocene-catalyzed olefin thermoplastic elastomer, 15 kg of ethylene-propylene rubber, 5 kg of azobisisobutyronitrile, 1.98 kg of zinc oxide and 0.02 kg of zinc stearate, 8 kg of aluminum hydroxide and 2 kg of magnesium hydroxide, 1 kg of nano calcium carbonate, and 3 kg of black masterbatch into a 100 °C internal mixer and mix for 1 h, then pelletize to obtain the foaming masterbatch; S4. Pre-mix the foaming masterbatch prepared in S3, 10 kg of metallocene-catalyzed olefin thermoplastic elastomer, 15 kg of ethylene-propylene rubber, and 3 kg of black masterbatch in a 70 °C high-speed mixer for 2 h, then discharge them into a single-screw extruder for extrusion. The temperature of the extruder is set as follows: zone 1 at 120 °C, zone 2 at 130 °C, zone 3 at 135 °C, zone 4 at 140 °C, zone 5 at 145 °C, zone 6 at 150 °C, and the die temperature is 140 °C. Finally, wind up to obtain the mother roll; S5. Carry out 100 KeV electron irradiation on the mother roll prepared in S4 for 20 min for cross-linking; S6. Carry out horizontal furnace foaming on the cross-linked mother roll in S5 at a foaming temperature of 250 °C to obtain a heat-insulating and sound-absorbing lightweight foamed material.

[0068] Among them, the modifier is trans-1-(3-carboxy-4-hydroxyphenyl)-2-(2,5-dihydroxyphenyl)ethylene.

[0069] The grafting agent is glycidyl methacrylate.

[0070] Test example Apparent density: The test of apparent density is carried out based on the test method recorded in GB / T6343-2009 "Plastics and Rubber - Determination of Apparent Density of Cellular Materials".

[0071] Tensile strength: The test of tensile strength is carried out based on the test method recorded in GB / T6344-2008 "Cellular Plastics - Determination of Tensile Strength and Elongation at Break".

[0072] Flame retardant grade: The test of flame retardant grade is carried out based on the test method recorded in the UL94HF-1 test standard.

[0073] Open cell ratio: The test of open cell ratio is carried out based on the test method recorded in ASTM D2856-A.

[0074] Sound absorption coefficient: The determination of sound absorption coefficient is carried out based on the method recorded in ISO354.

[0075] The test results are shown in Table 1: Table 1 By observing the test data in Table 1, it can be seen that the foamed material prepared by the present invention has excellent flame retardant performance and sound absorption performance. Compared with Example 1, 5, and 6, in Comparative Example 1, the sound absorption coefficient and the open cell rate of the lightweight foamed material with heat insulation and sound absorption without thermoplastic elastomer and rubber are lower. Compared with Example 2, 3, and 4, in Comparative Example 2, the sound absorption coefficient and the open cell rate of the lightweight foamed material with heat insulation and sound absorption without thermoplastic elastomer and rubber are both lower. By comparing Examples 1-8, it can be seen that the sound absorption coefficients of Example 4 and Example 5 are relatively excellent. The possible reason for the sound absorption coefficient is due to the differences in the raw materials used and the process parameters during the preparation of the lightweight foamed material.

[0076] By observing the tensile strength test data in Table 1, it can be seen that among Examples 1-10 and Comparative Examples 1-4, the test result data of the tensile strength of Example 7 is better, indicating that the mechanical properties of the lightweight foamed material with heat insulation and sound absorption prepared in Example 7 are the best. Comparing the tensile strength test results of Examples 7-9 and Comparative Example 3, it is found that the tensile strength data are different. The reason for the data difference may be the use of different modifiers. The role of the modifier is that the phenolic hydroxyl group in the modifier can undergo a ring-opening reaction with the epoxy group on the grafting agent, so that the modifier can be fixed on the polypropylene chain segment by reacting with the grafting agent already grafted on the polypropylene chain segment, thereby modifying the polypropylene and affecting the tensile strength of the polypropylene. The reason for the different tensile strengths of the lightweight foamed materials prepared in Examples 7-9 and Comparative Example 3 may be that different modifiers are used in Examples 7-9 and Comparative Example 3. The modifier in Example 7 contains double bonds and carboxyl functional groups in addition to the reaction of the phenolic hydroxyl group with the grafting agent. The double bond can directly react with the polypropylene chain segment, thereby increasing the crosslinking degree and molecular weight of the modified polypropylene polymer. The carboxyl functional group can react with the hydroxyl functional group contained in the hydroxyapatite, thereby increasing the solubility of the hydroxyapatite in the modified polypropylene material and further improving the mechanical properties of the prepared lightweight foamed material with heat insulation and sound absorption.

[0077] Compared with the tensile strength test results in Example 7, Example 10 and Comparative Example 4, the mechanical properties of the heat-insulating and sound-absorbing lightweight foam material prepared in the examples are the best. Comparison found that different grafting agents were used. The role of the grafting agent is that diisopropylbenzene peroxide decomposes under heat to form free radicals, and then the primary free radicals capture the hydrogen atoms on the polymer to form macromolecular free radicals. Styrene can quickly react with polypropylene macromolecular free radicals to form stable polypropylene styrene free radicals, and then the polypropylene styrene free radicals react with the grafting agent, and the grafting agent reacts with the modifier, so that the modifier is grafted on the polypropylene segment through the grafting base. The reason for the different tensile strengths of the lightweight foam materials prepared in Example 7, Example 10 and Comparative Example 4 may be that different grafting agents were used in Example 7, Example 10 and Comparative Example 4. Compared with the grafting agents in Example 7, Example 10 and Comparative Example 4, the grafting agent in Example 7 also contains double bonds and triple bonds. The double bond and triple bond functional groups can undergo addition reactions with the phenolic hydroxyl functional groups contained in the modifier, thereby affecting the content of the modifier grafted on the polypropylene chain segment. Since the content of the modifier is indirectly controlled, and the modifier has a strong hydrogen supply ability, it can quench free radicals and stabilize the tertiary carbon free radicals of polypropylene. Therefore, when the content of the modifier is increased, the degradation of the modified polypropylene is inhibited, thereby making the mechanical properties of the modified polypropylene better, thereby making the tensile strength of the prepared heat-insulating and sound-absorbing lightweight foam material better.

Claims

1. A lightweight foamed material with heat insulation and sound absorption characteristics, characterized in that, It comprises the following components in parts by weight: 40 - 120 parts of polyolefin resin, and / or 10 - 60 parts of polyolefin copolymer, 1 - 40 parts of foaming agent, 1 - 20 parts of flame retardant, 1 - 20 parts of foaming aid, 1 - 20 parts of filler, 1 - 5 parts of masterbatch, and / or 1 - 30 parts of thermoplastic elastomer, and / or 1 - 30 parts of rubber.

2. The heat-insulating and sound-absorbing lightweight foamed material according to claim 1, wherein The polyolefin resin is at least one of low-density polyethylene, high-density polyethylene, and polypropylene; the polyolefin copolymer is ethylene-vinyl acetate copolymer.

3. The heat-insulating and sound-absorbing lightweight foamed material according to claim 1, wherein The foaming agent is any one of azodicarbonamide, azobisisobutyronitrile, and barium azodicarboxylate; the foaming aid is a mixture of zinc oxide and zinc stearate, and the mass ratio of zinc oxide to zinc stearate is 99:

1.

4. The heat-insulating and sound-absorbing lightweight foamed material according to claim 1, characterized in that, The flame retardant is one or a mixture of trichloroethyl phosphate, trichloropropyl phosphate, expanded graphite, aluminum hydroxide, and magnesium hydroxide.

5. The heat-insulating and sound-absorbing lightweight foamed material according to claim 1, wherein The filler is any one or a mixture of two of nano calcium carbonate with a particle size of 0.01 - 0.1 μm and ultrafine talcum powder with a particle size of 0.1 - 10 μm.

6. The lightweight foamed material for heat insulation and sound absorption according to claim 1, characterized in that, The thermoplastic elastomer is one or a mixture of two of diene-based thermoplastic elastomer or metallocene-catalyzed polyolefin-based thermoplastic elastomer.

7. The heat-insulating and sound-absorbing lightweight foamed material according to claim 1, characterized in that, The rubber is any one or a mixture of several of ethylene-propylene rubber, nitrile rubber, styrene-butadiene rubber, and silicone rubber.

8. The heat-insulating and sound-absorbing lightweight foamed material according to claim 2, characterized in that, The melt index of the low-density polyethylene is 0.5 - 4.0 g / 10min, the melt index of the high-density polyethylene is 0.5 - 6.0 g / 10min, the melt index of the polypropylene is 2 - 15 g / 10min; the melt index of the ethylene-vinyl acetate copolymer is 0.5 - 8 g / 10min.

9. The heat-insulating and sound-absorbing lightweight foamed material according to claim 6, wherein, The diene-based thermoplastic elastomer is a mixture of 1,4-trans-polyisoprene rubber and 1,1,4,4-tolyl-1,3-butadiene.

10. The preparation method of any one of the heat-insulating and sound-absorbing lightweight foamed materials according to claims 1-9, characterized in that, It comprises the following steps, in parts by weight: S1. Weigh 40 - 120 parts of polyolefin resin, and / or 10 - 60 parts of polyolefin copolymer, 1 - 30 parts of thermoplastic elastomer, 1 - 30 parts of rubber, 1 - 40 parts of foaming agent, 1 - 20 parts of flame retardant, 1 - 20 parts of foaming aid, 1 - 20 parts of filler, 1 - 5 parts of masterbatch to obtain a mixed raw material; S2. Kneading and pelletizing: Pour the mixed raw material prepared in S1 into a mixer to mix and pelletize to obtain masterbatch; S3. Extruding mother sheet: Pre-mix and dry the masterbatch prepared in S2, and then send it into a single-screw extruder to extrude into sheets and wind to obtain a mother roll; S4. Irradiation crosslinking: Perform electron irradiation crosslinking with an energy of 30 keV - 100 keV on the mother roll obtained in S3 to obtain a crosslinked mother roll; S5. Foaming: Carry out temperature-raising foaming, trimming, and winding on the crosslinked mother roll obtained in S4 in a horizontal foaming furnace to obtain a polyolefin open-cell sound-absorbing foamed material.

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