High-impact-resistance PVC (polyvinyl chloride) composite mute pipe and preparation method thereof

Abstract

The invention belongs to the technical field of plastic pipelines, and particularly discloses a high-impact-resistance PVC composite mute pipe which comprises an inner layer, a foaming sound insulation layer, a hollow silencing layer and an outer layer which are sequentially arranged from inside to outside. The inner layer comprises an inner layer body and a plurality of flow guide screw flights, and the flow guide screw flights are distributed in the circumferential direction of the inner circumference of the inner layer body at intervals. A plurality of silencing holes are formed in the front side face of the hollow silencing layer in the circumferential direction. According to the high-impact-resistance PVC composite mute pipe and the preparation method thereof, the high-impact-resistance PVC composite mute pipe has high strength and high and low temperature impact resistance, and a good noise reduction effect can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic pipes, and in particular relates to a high-impact PVC composite silent pipe and a preparation method thereof. Background Art

[0002] As people's requirements for the quality of life are getting higher and higher, the drainage noise problem of buildings has also received more and more attention. The noise source in building drainage mainly comes from the collision between water beams, water beams and pipe walls, airflow during the water flow process, and the noise generated by the change of water flow section or water flow direction. Therefore, the industry has launched a series of silencer drainage pipes: for example, PVC solid wall spiral pipes mainly guide water flow through the spiral ribs on the inner wall to reduce water flow impact, but the noise reduction effect is very limited; PVC hollow spiral pipes have the combined effect of inner wall spiral rib drainage and hollow layer cavity structure sound insulation, and the noise reduction effect is better than solid wall spiral pipes, which can reduce 8 to 10 dB compared with standard solid wall pipes, but the physical properties of the connecting ribs forming the cavity are low, and the impact resistance of the pipe is poor; the composite structure PVC core layer foam pipe has the problem of low overall mechanical strength of the pipe and unclear noise reduction effect. Therefore, it is necessary to provide a PVC silent drainage pipe with better sound insulation and noise reduction effect than ordinary PVC-U hollow spiral pipes, high mechanical strength, especially significantly improved impact resistance, and easy extrusion and processing.

[0003] Invention patent CN111662520A discloses a hollow spiral tube and its preparation method, which uses carboxyl nitrile rubber powder and resin for physical cross-linking to improve the toughness of the tube, but the impact resistance of the tube is still insufficient, and the sound insulation performance needs to be further improved. Utility model patent CN208703327U discloses a sound-absorbing drainage pipe, the tube body is composed of a solid wall PVC inner layer, a first honeycomb cavity PVC sound-absorbing layer, an asbestos board sound-absorbing layer, a second honeycomb cavity PVC sound-absorbing layer and a solid wall PVC outer layer from the inside to the outside, and 12 spiral groove guide ribs are evenly distributed on the inner wall of the inner layer. The sound insulation effect of this solution is significant, but the strength of the structure is insufficient, the drop hammer impact performance is poor, and the molding is complex. Summary of the invention

[0004] The purpose of the present invention is to overcome the above problems existing in the prior art and to provide a high-impact PVC composite silent pipe and a preparation method thereof. The high-impact PVC composite silent pipe has high strength and high and low temperature impact resistance, and can achieve good noise reduction effect.

[0005] In order to achieve the above technical objectives and the above technical effects, the present invention is implemented through the following technical solutions:

[0006] In a first aspect, the present invention provides a high-impact PVC composite silent pipe, comprising an inner layer, a foamed sound insulation layer, a hollow sound-absorbing layer and an outer layer arranged in sequence from the inside to the outside;

[0007] The inner layer includes an inner layer body and a plurality of guide screw ribs, wherein the plurality of guide screw ribs are distributed at intervals along the circumference of the inner circumference of the inner layer body;

[0008] A plurality of sound-absorbing holes are provided on the front side of the hollow sound-absorbing layer along the circumferential direction;

[0009] The raw material components and weight ratios of the inner layer and the hollow sound-absorbing layer are the same. The raw materials of the inner layer include, by weight: 100 parts of SG-5 polyvinyl chloride resin, 15 to 30 parts of filler, 2.6 to 3.6 parts of calcium zinc stabilizer, 0.6 to 1.5 parts of lubricant, 0.8 to 2.2 parts of processing aid, 3 to 10 parts of impact modifier, and 1.5 to 2.5 parts of titanium dioxide;

[0010] The raw materials of the foamed sound insulation layer include, by weight: 100 parts of SG-7 polyvinyl chloride resin, 2.5-3.5 parts of calcium zinc stabilizer, 0.6-1.4 parts of lubricant, 3-7 parts of impact modifier, 0.5-2 parts of titanium dioxide, 5-12 parts of nucleating agent, 0.3-0.5 parts of foaming agent, and 4-8 parts of foaming regulator;

[0011] The raw materials of the outer layer include, by weight: 60 to 90 parts of SG-5 polyvinyl chloride resin, 25 to 50 parts of acrylic copolymer polyvinyl chloride resin, 2.8 to 4 parts of calcium zinc stabilizer, 4 to 12 parts of impact modifier, 0 to 12 parts of filler, 0.6 to 1.6 parts of lubricant, 1.0 to 2.5 parts of processing aid, and 1.5 to 2.5 parts of titanium dioxide.

[0012] Furthermore, the thickness of the inner layer body is 0.7 to 1.3 mm;

[0013] The thickness of the foamed sound insulation layer is 1.75 to 1.9 mm;

[0014] The thickness of the hollow sound-absorbing layer is not less than 3.8 mm;

[0015] The thickness of the outer layer is not less than 2 mm.

[0016] Furthermore, the guide screw fins are distributed in a spiral shape;

[0017] The number of the guide spiral fins is 4 to 12.

[0018] Furthermore, the number of the muffler holes is 20 to 40;

[0019] The vertical section of the muffler hole is elliptical.

[0020] Furthermore, the impact modifier is any one or more of chlorinated polyethylene, MBS, impact-resistant ACR, and nitrile rubber powder mixed in any proportion.

[0021] Furthermore, the filler is any one or more of light calcium carbonate, heavy calcium carbonate, nano calcium carbonate, barium sulfate, and white carbon black mixed in any proportion;

[0022] The lubricant is a lipid lubricant and / or a wax lubricant;

[0023] The processing aid is any one or more of methyl methacrylate / acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / vinyl acetate copolymer, and acrylonitrile / styrene copolymer, mixed in any proportion.

[0024] Furthermore, the lipid lubricant includes one or more of stearic acid, octadecyl alcohol, fatty acid ester, fatty acid metal soap, and polyol fatty acid amide mixed in any proportion;

[0025] The wax lubricant includes any one or more of oxidized polyethylene wax, polyethylene wax, and paraffin wax mixed in any proportion.

[0026] Further, the foaming agent is azodicarbonamide;

[0027] The nucleating agent is heavy calcium carbonate or nano calcium carbonate;

[0028] The foaming regulator is an acrylic acid ester processing aid.

[0029] In a second aspect, the present invention provides a method for preparing a high-impact PVC composite silent pipe, the preparation method comprising the following steps:

[0030] S1: Weigh the raw materials of the inner layer, the foamed sound insulation layer, the hollow sound absorbing layer and the outer layer respectively, put the weighed raw materials of the inner layer, the foamed sound insulation layer, the hollow sound absorbing layer and the outer layer into a high-speed mixing unit for mixing, first perform hot mixing, then perform cold mixing, and finally perform screening and aging to prepare a rigid polyvinyl chloride inner layer mixed material, a foamed sound insulation layer mixed material, a rigid polyvinyl chloride hollow sound absorbing layer mixed material and a modified polyvinyl chloride outer layer mixed material;

[0031] S2: plasticizing the prepared rigid polyvinyl chloride inner layer mixed material, foamed sound insulation layer mixed material, rigid polyvinyl chloride hollow sound-absorbing layer mixed material and modified polyvinyl chloride outer layer mixed material through a conical twin-screw extruder respectively, and then compounding and molding them in a multi-layer co-extrusion die to prepare a blank;

[0032] Among them, the barrel temperature of the conical twin-screw extruder is 165-185°C, the temperature of the die body of the multi-layer co-extrusion die is 170-190°C, and the temperature at the outlet of the multi-layer co-extrusion die is 195-208°C;

[0033] S3: The blank enters a vacuum shaping cooling box and is cooled and shaped by internal pressure and external sizing to produce a high-impact PVC composite silent pipe.

[0034] Furthermore, in step S1, during the mixing process of the raw materials of the inner layer, the hollow sound-absorbing layer and the outer layer in the high-speed mixing unit, the hot mixing temperature is 120-130° C., and the cold mixing temperature is 45-50° C.;

[0035] During the mixing process of the raw materials of the foamed sound insulation layer in the high-speed mixing unit, the hot mixing temperature is 110-118° C. and the cold mixing temperature is 40-46° C.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The high-impact PVC composite silent pipe provided by the present invention has the characteristics of high strength and excellent high and low temperature impact resistance, and its hollow structure has a good noise reduction effect.

[0038] 2. In the present invention, the outer layer of the pipe, i.e., the modified polyvinyl chloride outer layer, is made of a blend of SG-5 type polyvinyl chloride resin and acrylic copolymer polyvinyl chloride (AGR) resin in its raw material composition, and has the advantages of high pressure resistance, high and low temperature toughness, and high and low temperature impact resistance; at the same time, an impact modifier is used, and the impact modifier is any one or more of chlorinated polyethylene, MBS, impact-resistant ACR (methyl methacrylate / acrylate copolymer), and nitrile rubber powder mixed in any proportion. Therefore, the modified polyvinyl chloride outer layer also uses chlorinated polyethylene (CPE) and MBS (a terpolymer of methyl methacrylate (M), butadiene (B) and styrene (S)), ACR resin or nitrile rubber powder to form a composite toughening system, which further improves the low-temperature impact resistance of the pipe.

[0039] 3. In the present invention, the silencer holes of the rigid polyvinyl chloride hollow silencer layer are of an elliptical structure, which significantly reduces the shrinkage stress generated by the melt at the connecting ribs during molding compared to the traditional rectangular structure, thereby avoiding the influence on the impact resistance of the pipe.

[0040] 4. In the present invention, the high-impact PVC composite silent pipe has good sound insulation and noise reduction effects. Specifically, the inner layer of the pipe, that is, the rigid polyvinyl chloride inner layer, has multiple guide spiral ridges on the inner layer body that can guide the water to flow downward through the inner wall in a spiral shape, so that an unobstructed air column is formed in the middle part of the pipe, which increases the water flow rate while reducing turbulent noise; the multi-layer composite structure, the foamed sound insulation layer and the rigid polyvinyl chloride hollow sound-absorbing layer greatly reduce the transmission of drainage noise to the outside of the pipe, while reducing the weight of the pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0042] Figure 1 It is a schematic diagram of the structure of the present invention;

[0043] Figure 2 It is a partial structural schematic diagram of the present invention.

[0044] Among them, the figures are marked as: 1, outer layer; 2, hollow sound-absorbing layer; 3, foamed sound-insulating layer; 4, inner layer; 40, inner layer body; 5, sound-absorbing hole; 6, guide spiral rib. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "all around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0047] First, as Figure 1 to Figure 2 As shown, an embodiment of the present invention provides a high-impact PVC composite silent pipe, comprising an inner layer 4, a foamed sound insulation layer 3, a hollow sound-absorbing layer 2 and an outer layer 1 arranged in sequence from the inside to the outside;

[0048] The inner layer 4 includes an inner layer body 40 and a plurality of guide spiral ridges 6, wherein the plurality of guide spiral ridges 6 are distributed at intervals along the circumference of the inner circumference of the inner layer body 40; wherein the guide spiral ridges 6 are distributed in a spiral shape, specifically, the guide spiral ridges 6 are distributed in a counterclockwise spiral shape; the number of the guide spiral ridges 6 is 4 to 12, specifically, the number of the guide spiral ridges 6 is 6;

[0049] The thickness of the inner body 40 is 0.7-1.3 mm; the height of the guide screw fin 6 is not less than 1.5 mm;

[0050] The density of the foamed sound insulation layer 3 is 0.8 to 1.0 g / cm 3 , its thickness is 1.75~1.9mm;

[0051] The thickness of the hollow sound-absorbing layer 2 is not less than 3.8 mm; and a plurality of sound-absorbing holes 5 are provided on the front side of the hollow sound-absorbing layer 2 along the circumferential direction, and the vertical cross-section of the sound-absorbing holes 5 is elliptical; the number of the sound-absorbing holes 5 is 20 to 40; the sound-absorbing holes 5 are elliptical structures, which significantly reduce the shrinkage stress generated by the melt at the connecting ribs during molding compared to the traditional rectangular structure, and avoid the impact on the impact resistance of the pipe;

[0052] The thickness of the outer layer 1 is not less than 2 mm;

[0053] The raw material components and weight ratios of the inner layer 4 and the hollow sound-absorbing layer 2 are the same;

[0054] The raw materials of the inner layer 4 include, by weight: 100 parts of SG-5 type polyvinyl chloride resin, 15 to 30 parts of filler, 2.6 to 3.6 parts of calcium zinc stabilizer, 0.6 to 1.5 parts of lubricant, 0.8 to 2.2 parts of processing aid, 3 to 10 parts of impact modifier, and 1.5 to 2.5 parts of titanium dioxide;

[0055] The raw materials of the foamed sound insulation layer 3 include, by weight: 100 parts of SG-7 type polyvinyl chloride resin, 2.5-3.5 parts of calcium zinc stabilizer, 0.6-1.4 parts of lubricant, 3-7 parts of impact modifier, 0.5-2 parts of titanium dioxide, 5-12 parts of nucleating agent, 0.3-0.5 parts of foaming agent, and 4-8 parts of foaming regulator;

[0056] The raw materials of the outer layer 1 include, by weight: 60-90 parts of SG-5 type polyvinyl chloride resin, 25-50 parts of acrylic copolymer polyvinyl chloride resin, 2.8-4 parts of calcium zinc stabilizer, 4-12 parts of impact modifier, 0-12 parts of filler, 0.6-1.6 parts of lubricant, 1.0-2.5 parts of processing aid, and 1.5-2.5 parts of titanium dioxide;

[0057] Among them, in the raw material composition of the outer layer 1, the addition amount of the impact modifier is preferably 6.0 to 8.0 parts;

[0058] In the raw material composition of the inner layer 4, the foamed sound insulation layer 3, the hollow sound-absorbing layer 2 and the outer layer 1, the impact modifier is any one or more of chlorinated polyethylene, MBS, impact-resistant ACR, and nitrile rubber powder mixed in any proportion; specifically, the impact modifier can be selected from a mixture of any two of chlorinated polyethylene, MBS, impact-resistant ACR, and nitrile rubber powder;

[0059] The fillers are any one or more of light calcium carbonate, heavy calcium carbonate, nano calcium carbonate, barium sulfate, and white carbon black mixed in any proportion; wherein the heavy calcium carbonate is heavy calcium carbonate with a mesh size of more than 2000;

[0060] In the raw material composition of the inner layer 4, the hollow sound-absorbing layer 2, and the outer layer 1, the lubricants are all fat lubricants and / or wax lubricants, that is, the lubricants are all any one of fat lubricants and wax lubricants, or the lubricants are all a mixture of fat lubricants and wax lubricants in any proportion; specifically, the fat lubricant includes one or more of stearic acid, octadecyl alcohol, fatty acid ester, fatty acid metal soap, and polyol fatty acid amide mixed in any proportion, and the wax lubricant includes any one or more of oxidized polyethylene wax, polyethylene wax, and paraffin mixed in any proportion;

[0061] The processing aids are any one or more of methyl methacrylate / acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / vinyl acetate copolymer, and acrylonitrile / styrene copolymer mixed in any proportion;

[0062] In the raw material composition of the foamed sound insulation layer 3, the foaming agent is azodicarbonamide (AC);

[0063] The nucleating agent is heavy calcium carbonate or nano calcium carbonate, wherein the heavy calcium carbonate is selected to be heavy calcium carbonate with a mesh size of 2500 or more;

[0064] The foaming regulator is an acrylic acid ester processing aid; specifically, the foaming regulator is an acrylic acid ester processing aid with an intrinsic viscosity greater than 11 mPa·s;

[0065] In a second aspect, an embodiment of the present invention provides a method for preparing a high-impact PVC composite silent pipe, the preparation method comprising the following steps:

[0066] S1: Weigh the raw materials of the inner layer 4, the foamed sound insulation layer 3, the hollow sound absorbing layer 2 and the outer layer 1 respectively, put the weighed raw materials of the inner layer 4, the foamed sound insulation layer 3, the hollow sound absorbing layer 2 and the outer layer 1 into a high-speed mixing unit for mixing, first hot mixing, then cold mixing, and finally screening and aging to prepare a rigid polyvinyl chloride inner layer mixed material, a foamed sound insulation layer mixed material, a rigid polyvinyl chloride hollow sound absorbing layer mixed material and a modified polyvinyl chloride outer layer mixed material;

[0067] In step S1, during the mixing process of the raw materials of the inner layer 4, the hollow sound-absorbing layer 2 and the outer layer 1 in the high-speed mixing unit, the hot mixing temperature is 120-130°C and the cold mixing temperature is 45-50°C;

[0068] During the mixing process of the raw materials of the foamed sound insulation layer 3 in the high-speed mixing unit, the hot mixing temperature is 110-118°C and the cold mixing temperature is 40-46°C;

[0069] S2: plasticizing the prepared rigid polyvinyl chloride inner layer mixed material, foamed sound insulation layer mixed material, rigid polyvinyl chloride hollow sound-absorbing layer mixed material and modified polyvinyl chloride outer layer mixed material through a conical twin-screw extruder respectively, and then compounding and molding them in a multi-layer co-extrusion die to prepare a blank;

[0070] Among them, the barrel temperature of the conical twin-screw extruder is 165-185°C, the temperature of the die body of the multi-layer co-extrusion die is 170-190°C, and the temperature at the outlet of the multi-layer co-extrusion die is 195-208°C;

[0071] S3: The blank enters a vacuum shaping cooling box and is cooled and shaped by internal pressure and external sizing to produce a high-impact PVC composite silent pipe.

[0072] The following are specific examples. In the following examples, unless otherwise specified, all raw materials can be obtained from commercial sources.

[0073] Example 1

[0074] The present embodiment provides a high-impact PVC composite silent pipe, comprising an inner layer 4, a foamed sound insulation layer 3, a hollow sound absorbing layer 2 and an outer layer 1 arranged in sequence from the inside to the outside, wherein the thickness of the inner layer 4 is about 0.9 mm, and there are 6 spiral guide spiral ridges 6 on the inner layer 4, and the height of the guide spiral ridges 6 is about 1.7 mm; the density of the foamed sound insulation layer 3 is about 1.0 g / cm 3 , thickness is about 1.8mm; the height of the hollow layer structure is 4.0-4.2mm, the number of elliptical silencer holes is 28; the wall thickness of the outer layer 1 is 2.3-2.4mm;

[0075] The raw materials of the inner layer 4 and the hollow sound-absorbing layer 2 include, by weight: 100 parts of SG-5 polyvinyl chloride resin; 22 parts of filler (light calcium carbonate); 2.9 parts of calcium zinc stabilizer; 0.62 parts of polyethylene wax; 1.6 parts of processing aid (ACR processing aid); 6 parts of chlorinated polyethylene; 2.5 parts of MBS resin; 2 parts of rutile titanium dioxide;

[0076] The raw materials of the foamed sound insulation layer 3 include, by weight: 100 parts of SG-7 polyvinyl chloride resin; 3 parts of calcium zinc stabilizer; 0.2 parts of oxidized polyethylene wax; 0.45 parts of polyethylene wax; 6 parts of chlorinated polyethylene; 0.5 parts of titanium dioxide; 10 parts of nucleating agent (nano calcium carbonate); 0.36 parts of foaming agent (AC); 6 parts of foaming regulator (ACR foaming regulator);

[0077] The raw materials of the outer layer 1 include, by weight: 80 parts of SG-5 polyvinyl chloride resin; 30 parts of AGR resin; 3.2 parts of calcium zinc stabilizer; 3.2 parts of MBS resin; 3.7 parts of impact-resistant ACR resin; 5 parts of filler (light calcium carbonate); 0.6 parts of distearyl phthalate; 0.1 parts of oxidized polyethylene wax; 0.6 parts of polyethylene wax; 1.4 parts of processing aid (ACR processing aid); 2 parts of titanium dioxide;

[0078] Among them, the calcium zinc stabilizer was purchased from Zhejiang Chuanhua Huayang Chemical Co., Ltd., model: TF-C6.

[0079] This embodiment also provides a method for preparing a high-impact PVC composite silent pipe, the method comprising the following steps:

[0080] S1: Weigh the raw materials of the inner layer 4, the foamed sound insulation layer 3, the hollow sound absorbing layer 2 and the outer layer 1 respectively, put the weighed raw materials of the inner layer 4, the foamed sound insulation layer 3, the hollow sound absorbing layer 2 and the outer layer 1 into a high-speed mixing unit for mixing, first perform hot mixing, then perform cold mixing, and finally perform screening and aging for 12 hours to prepare a rigid polyvinyl chloride inner layer mixed material, a foamed sound insulation layer mixed material, a rigid polyvinyl chloride hollow sound absorbing layer mixed material and a modified polyvinyl chloride outer layer mixed material;

[0081] In step S1, during the mixing process of the raw materials of the inner layer 4, the hollow sound-absorbing layer 2 and the outer layer 1 in the high-speed mixing unit, the hot mixing temperature is 125°C and the cold mixing temperature is 45°C;

[0082] During the mixing process of the raw materials of the foamed sound insulation layer 3 in the high-speed mixing unit, the hot mixing temperature is 115°C and the cold mixing temperature is 42°C;

[0083] S2: plasticizing the prepared rigid polyvinyl chloride inner layer mixture, foamed sound insulation layer mixture, rigid polyvinyl chloride hollow sound-absorbing layer mixture and modified polyvinyl chloride outer layer mixture through an 80 conical twin-screw extruder, and then compounding and molding in a four-layer co-extrusion mold to prepare a blank;

[0084] Among them, the temperatures of the four zones of the conical twin-screw extruder barrel are 170±5℃, 175±3℃, 168±3℃, and 165℃, respectively; the temperature of the die body of the four-layer co-extrusion die is 180±8℃, and the temperature at the exit of the four-layer co-extrusion die is 202℃;

[0085] S3: The blank enters a vacuum shaping cooling box and is cooled and shaped by internal pressure and external sizing to obtain a composite silent pipe.

[0086] Example 2

[0087] This embodiment provides a high-impact PVC composite silent pipe, which is different from the embodiment 1 in that, in this embodiment, the wall thickness of the inner layer 4 is about 0.9 mm, there are 12 spiral guide spiral ridges 6 on the inner layer 4, and the height of the guide spiral ridges 6 is about 1.7 mm; the density of the foamed sound insulation layer 3 is about 1.0 g / cm 3 , thickness is about 1.9mm; the height of the hollow sound-absorbing layer 2 is 4.0-4.2mm, the number of the elliptical sound-absorbing holes 5 is 36; the wall thickness of the outer layer 1 is 2.3-2.4mm;

[0088] This embodiment also provides a method for preparing a high-impact PVC composite silent pipe, and the preparation method is carried out with reference to the method for preparing a high-impact PVC composite silent pipe provided in Example 1.

[0089] Example 3

[0090] This embodiment provides a high-impact PVC composite silent pipe, which is different from Embodiment 1 in that:

[0091] The raw materials of the inner layer 4 and the hollow sound-absorbing layer 2 include, by weight: 100 parts of SG-5 polyvinyl chloride resin; 18 parts of filler (light calcium carbonate); 2.8 parts of calcium zinc stabilizer; 0.6 parts of polyethylene wax; 1.8 parts of processing aid (ACR processing aid); 6 parts of chlorinated polyethylene; 2.5 parts of nitrile rubber powder; 2 parts of rutile titanium dioxide;

[0092] The raw materials of the foamed sound insulation layer 3 include, by weight: 100 parts of SG-7 polyvinyl chloride resin; 3 parts of calcium zinc stabilizer; 0.2 parts of oxidized polyethylene wax; 0.5 parts of polyethylene wax; 4 parts of nitrile rubber powder; 1.2 parts of titanium dioxide; 12 parts of nucleating agent (nano calcium carbonate); 0.3 parts of foaming agent (AC); 6.5 parts of foaming regulator (ACR foaming regulator);

[0093] The raw materials of the outer layer 1 include, by weight: 65 parts of SG-5 polyvinyl chloride resin; 38 parts of AGR resin; 3.4 parts of calcium zinc stabilizer; 3 parts of MBS resin; 4 parts of impact-resistant ACR resin; 6 parts of filler (nano calcium carbonate); 0.8 parts of distearyl phthalate; 0.1 parts of oxidized polyethylene wax; 0.65 parts of polyethylene wax; 1.5 parts of processing aid (ACR processing aid); 2 parts of titanium dioxide;

[0094] Among them, the calcium zinc stabilizer was purchased from Zhejiang Chuanhua Huayang Chemical Co., Ltd., model: TF-C6.

[0095] This embodiment also provides a method for preparing a high-impact PVC composite silent pipe, and the preparation method is carried out with reference to the method for preparing a high-impact PVC composite silent pipe provided in Example 1.

[0096] Example 4

[0097] The present embodiment provides a high-impact PVC composite silent pipe, comprising an inner layer 4, a foamed sound insulation layer 3, a hollow sound absorbing layer 2 and an outer layer 1 arranged in sequence from the inside to the outside, wherein the thickness of the inner layer 4 is about 0.7 mm, and there are 12 spiral guide spiral ridges 6 on the inner layer 4, and the height of the guide spiral ridges 6 is about 1.7 mm; the density of the foamed sound insulation layer 3 is about 0.80 g / cm 3 , thickness is about 1.9mm; the structure height of the hollow sound-absorbing layer 2 is about 3.8-4.0mm, and the number of elliptical sound-absorbing holes is 36; the wall thickness of the outer layer 1 is 2.0-2.15mm;

[0098] The raw materials of the inner layer 4 and the hollow sound-absorbing layer 2 include, by weight: 100 parts of SG-5 polyvinyl chloride resin; 15 parts of filler (light calcium carbonate); 3.6 parts of calcium zinc stabilizer; 0.5 parts of stearic acid; 0.25 parts of oxidized polyethylene wax; 0.75 parts of polyethylene wax; 0.8 parts of processing aid (ACR processing aid); 6 parts of chlorinated polyethylene; 4 parts of MBS resin; 1.5 parts of rutile titanium dioxide;

[0099] The raw materials of the foamed sound insulation layer 3 include, by weight: 100 parts of SG-7 polyvinyl chloride resin; 3.5 parts of calcium zinc stabilizer; 0.2 parts of oxidized polyethylene wax; 0.4 parts of polyethylene wax; 7 parts of chlorinated polyethylene; 0.5 parts of titanium dioxide; 12 parts of nucleating agent (nano calcium carbonate); 0.45 parts of foaming agent (AC); 8 parts of foaming regulator (ACR foaming regulator);

[0100] The raw materials of the outer layer 1 include, by weight: 60 parts of SG-5 polyvinyl chloride resin; 50 parts of AGR resin; 4 parts of calcium zinc stabilizer; 4.8 parts of MBS resin; 3.2 parts of impact-resistant ACR resin; 0.6 parts of distearyl phthalate; 0.4 parts of oxidized polyethylene wax; 0.6 parts of polyethylene wax; 1.0 parts of processing aid (ACR processing aid is selected); 1.5 parts of titanium dioxide;

[0101] Among them, the calcium zinc stabilizer was purchased from Zhejiang Chuanhua Huayang Chemical Co., Ltd., model: TF-C6.

[0102] This embodiment also provides a method for preparing a high-impact PVC composite silent pipe, and the preparation method is carried out with reference to the method for preparing a high-impact PVC composite silent pipe provided in Example 1.

[0103] Example 5

[0104] The present embodiment provides a high-impact PVC composite silent pipe, comprising an inner layer 4, a foamed sound insulation layer 3, a hollow sound absorbing layer 2 and an outer layer 1 arranged in sequence from the inside to the outside, wherein the thickness of the inner layer 4 is about 0.7 mm, and there are 6 spiral guide spiral ridges 6 on the inner layer 4, and the height of the guide spiral ridges 6 is about 1.7 mm; the density of the foamed sound insulation layer 3 is about 0.80 g / cm 3 , thickness is about 1.75mm; the structure height of the hollow sound-absorbing layer 2 is about 3.8-4.0mm, and the number of elliptical sound-absorbing holes is 28; the wall thickness of the outer layer 1 is about 2.0-2.15mm;

[0105] The raw materials of the inner layer 4 and the hollow sound-absorbing layer 2 include, by weight: 100 parts of SG-5 polyvinyl chloride resin; 30 parts of filler (light calcium carbonate); 2.6 parts of calcium zinc stabilizer; 0.6 parts of polyethylene wax; 2.2 parts of processing aid (ACR processing aid); 2 parts of chlorinated polyethylene; 1 part of MBS resin; 2.5 parts of rutile titanium dioxide;

[0106] The raw materials of the foamed sound insulation layer 3 include, by weight: 100 parts of SG-7 polyvinyl chloride resin; 2.5 parts of calcium zinc stabilizer; 0.5 parts of oxidized polyethylene wax; 0.9 parts of polyethylene wax; 3 parts of chlorinated polyethylene; 2 parts of titanium dioxide; 5 parts of nucleating agent (nano calcium carbonate); 0.5 parts of foaming agent (AC); 4 parts of foaming regulator (ACR foaming regulator);

[0107] The raw materials of the outer layer 1 include, by weight: 90 parts of SG-5 polyvinyl chloride resin; 25 parts of AGR resin; 2.8 parts of calcium zinc stabilizer; 3.5 parts of MBS resin; 2.5 parts of impact-resistant ACR resin; 12 parts of filler (light calcium carbonate); 0.25 parts of distearyl phthalate; 0.1 parts of oxidized polyethylene wax; 0.25 parts of polyethylene wax; 2.5 parts of processing aid (ACR processing aid); 2.5 parts of titanium dioxide;

[0108] Among them, the calcium zinc stabilizer was purchased from Zhejiang Chuanhua Huayang Chemical Co., Ltd., model: TF-C6.

[0109] This embodiment also provides a method for preparing a high-impact PVC composite silent pipe, and the preparation method is carried out with reference to the method for preparing a high-impact PVC composite silent pipe provided in Example 1.

[0110] Comparative Example 1

[0111] This comparative example provides a composite silent pipe, which is different from Example 1 in that the high-impact PVC composite silent pipe in this comparative example includes an inner layer 4, a hollow sound-absorbing layer 2 and an outer layer 1 arranged in sequence from the inside to the outside, that is, the foaming layer is removed, and the thickness and structure of the inner layer 4, the hollow sound-absorbing layer 2 and the outer layer 1 are the same as those of Example 1;

[0112] The inner layer 4 and the hollow sound-absorbing layer 2 are made of the same raw materials, which are collectively referred to as the inner layer below. The inner layer includes, by weight: 100 parts of SG-5 polyvinyl chloride resin; 25 parts of filler (light calcium carbonate); 3 parts of calcium zinc stabilizer; 0.65 parts of polyethylene wax; 2 parts of processing aid (ACR processing aid); 6.5 parts of chlorinated polyethylene; 2 parts of MBS resin; 2 parts of rutile titanium dioxide;

[0113] The raw materials of the outer layer 1 include, by weight: 80 parts of SG-5 polyvinyl chloride resin; 30 parts of AGR resin; 3.2 parts of calcium zinc stabilizer; 3.2 parts of MBS resin; 4 parts of impact-resistant ACR resin; 5 parts of filler (light calcium carbonate); 0.8 parts of distearyl phthalate; 0.23 parts of oxidized polyethylene wax; 0.55 parts of polyethylene wax; 1.4 parts of processing aid (ACR processing aid); 2 parts of titanium dioxide;

[0114] Among them, the calcium zinc stabilizer was purchased from Zhejiang Chuanhua Huayang Chemical Co., Ltd., model: TF-C6.

[0115] This comparative example also provides a method for preparing a composite silent pipe, which comprises the following steps:

[0116] S1: Weigh the raw materials of the inner layer and the outer layer 1 respectively, put the weighed raw materials of the inner layer and the outer layer 1 into a high-speed mixing unit for mixing, first perform hot mixing, then perform cold mixing, and finally perform screening and aging for 12 hours to prepare a mixed material of a rigid polyvinyl chloride inner layer and a mixed material of a modified polyvinyl chloride outer layer;

[0117] In step S1, during the mixing process of the raw materials of the inner layer and the outer layer 1 in the high-speed mixing unit, the hot mixing temperature is 125°C and the cold mixing temperature is 45°C;

[0118] S2: plasticizing the prepared hard polyvinyl chloride inner layer mixed material and modified polyvinyl chloride outer layer mixed material through an 80 conical twin-screw extruder respectively, and then compounding and molding them in a double-layer co-extrusion die to prepare a blank;

[0119] Among them, the temperatures of the four zones of the conical twin-screw extruder barrel are 170±5℃, 175±3℃, 168±3℃, and 165℃, respectively; the temperature of the die body of the four-layer co-extrusion die is 180±8℃, and the temperature at the exit of the four-layer co-extrusion die is 202℃;

[0120] S3: The blank enters a vacuum shaping cooling box and is cooled and shaped by internal pressure and external sizing to obtain a composite silent pipe.

[0121] Comparative Example 2

[0122] This comparative example provides a composite silent pipe, whose structure and thickness of each layer are the same as those in Example 1. The difference between this comparative example and Example 1 is that in this comparative example, the raw material components and weight ratios of the inner layer 4, the hollow sound-absorbing layer 2 and the outer layer 1 are the same, and each raw material component and weight ratio are made with reference to the raw material components and weight ratios of the inner layer 4 and the hollow sound-absorbing layer 2 in Example 1; the raw material components and weight ratios of the foamed sound insulation layer 3 are made with reference to the raw material components and weight ratios of the foamed sound insulation layer 3 in Example 1.

[0123] This comparative example also provides a method for preparing a composite silent pipe, which is carried out with reference to the method for preparing a high-impact PVC composite silent pipe provided in Example 1.

[0124] Results

[0125] The composite silent pipes prepared in the above embodiments and comparative examples, as well as PVC solid wall drainage pipes of the same specifications, were subjected to performance tests, and the relevant test contents are as follows:

[0126] Noise detection: Based on CJ / T 312-2009 "Noise test method for building drainage pipe system";

[0127] Drop hammer impact performance test: in accordance with GB / T 14152-2001 "Test method for external impact resistance of thermoplastic plastic pipes - clockwise rotation method";

[0128] The test results are shown in Table 1;

[0129] Table 1

[0130]

[0131]

[0132] In Table 1, the noise reduction range refers to the difference between the conducted noise performance value of the composite silent pipe provided in the embodiment and the comparative example and the conducted noise performance value of the PVC solid wall drainage pipe with the same outer diameter specification.

[0133] It can be seen from the data in Table 1 that the high-impact PVC composite silent pipe provided by the present invention can meet the conditions of 0°C, 4kg, and 2m without being broken by a falling hammer impact. Compared with PVC solid wall drainage pipes with the same outer diameter, the drainage noise reduction range of the PVC composite silent pipe of the present invention can reach more than 25dB; the pipe of comparative example 1 does not have a foamed sound insulation layer, and the sound insulation and noise reduction ability of the pipe is not ideal; the outer layer of the pipe of comparative example 2 is a traditional rigid polyvinyl chloride material, and the impact modification effect is not ideal;

[0134] In addition, after experiments, the ring stiffness of the PVC composite silent pipe prepared in the embodiment of the present invention can reach 10kN / m 2As shown above, in the flat test, the change rate of the outer diameter of the pipe in the vertical direction reaches 60%, and there is no crack on the inner and outer walls of the sample.

[0135] The high-impact PVC composite silent pipe provided by the present invention has high strength, especially high and low temperature impact resistance, and can achieve good sound insulation effect. The outer layer of the pipe uses a general polyvinyl chloride resin and an AGR resin to blend, and CPE and MBS, ACR resin or nitrile rubber powder are used to form a composite toughening agent, and the silencer hole of the hollow layer adopts an elliptical structure. The prepared pipe has the advantages of high pressure resistance, high and low temperature toughness and high and low temperature impact resistance. The drop hammer impact test can meet the conditions of 0°C, 4kg d90 hammer head, and 2m high drop hammer impact. The pipe does not break, and the real impact rate TIR is ≤5% under the conditions of -10°C, 3.2kg d90 hammer head, and 2m high drop hammer impact. The high-impact PVC composite silent pipe of the present invention has a good sound insulation and noise reduction effect through the drainage effect of multiple guide ribs on the inner wall, and adopts a multi-layer composite structure including a foamed sound insulation layer and a hollow sound-absorbing layer. Compared with PVC solid wall drainage pipes with the same outer diameter, the drainage noise reduction range of the PVC composite silent pipe of the present invention can reach 22 to 30 dB.

[0136] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0137] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A high impact PVC composite silent pipe, characterized in that: It comprises an inner layer (4), a foamed sound insulation layer (3), a hollow sound absorbing layer (2) and an outer layer (1) which are arranged in sequence from the inside to the outside; The inner layer (4) comprises an inner layer body (40) and a plurality of flow-guiding spiral ridges (6), wherein the plurality of flow-guiding spiral ridges (6) are distributed at intervals along the circumference of the inner circumference of the inner layer body (40); A plurality of sound-absorbing holes (5) are provided on the front side of the hollow sound-absorbing layer (2) along the circumferential direction; The raw material components and weight ratios of the inner layer (4) and the hollow sound-absorbing layer (2) are the same. The raw materials of the inner layer (4) include, by weight: 100 parts of SG-5 type polyvinyl chloride resin, 15 to 30 parts of filler, 2.6 to 3.6 parts of calcium zinc stabilizer, 0.6 to 1.5 parts of lubricant, 0.8 to 2.2 parts of processing aid, 3 to 10 parts of impact modifier, and 1.5 to 2.5 parts of titanium dioxide; The raw materials of the foamed sound insulation layer (3) include, by weight: 100 parts of SG-7 type polyvinyl chloride resin, 2.5-3.5 parts of calcium zinc stabilizer, 0.6-1.4 parts of lubricant, 3-7 parts of impact modifier, 0.5-2 parts of titanium dioxide, 5-12 parts of nucleating agent, 0.3-0.5 parts of foaming agent, and 4-8 parts of foaming regulator; The raw materials of the outer layer (1) include, by weight: 60 to 90 parts of SG-5 type polyvinyl chloride resin, 25 to 50 parts of acrylic copolymer polyvinyl chloride resin, 2.8 to 4 parts of calcium zinc stabilizer, 4 to 12 parts of impact modifier, 0 to 12 parts of filler, 0.6 to 1.6 parts of lubricant, 1.0 to 2.5 parts of processing aid, and 1.5 to 2.5 parts of titanium dioxide.

2. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The thickness of the inner layer body (40) is 0.7-1.3 mm; The thickness of the foamed sound insulation layer (3) is 1.75 to 1.9 mm; The thickness of the hollow sound-absorbing layer (2) is not less than 3.8 mm; The thickness of the outer layer (1) is not less than 2 mm.

3. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The guide screw fins (6) are distributed in a spiral shape; The number of the guide screw fins (6) is 4 to 12.

4. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The number of the muffler holes (5) is 20 to 40; The vertical cross section of the muffler hole (5) is elliptical.

5. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The impact modifier is any one or more of chlorinated polyethylene, MBS, impact-resistant ACR, and nitrile rubber powder mixed in any proportion.

6. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The filler is any one or more of light calcium carbonate, heavy calcium carbonate, nano calcium carbonate, barium sulfate, and white carbon black mixed in any proportion; The lubricant is a lipid lubricant and / or a wax lubricant; The processing aid is any one or more of methyl methacrylate / acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / vinyl acetate copolymer, and acrylonitrile / styrene copolymer, mixed in any proportion.

7. The high-impact PVC composite silent pipe according to claim 6, characterized in that: The lipid lubricant includes one or more of stearic acid, octadecyl alcohol, fatty acid ester, fatty acid metal soap, and polyol fatty acid amide, mixed in any proportion; The wax lubricant includes any one or more of oxidized polyethylene wax, polyethylene wax, and paraffin wax mixed in any proportion.

8. The high-impact PVC composite silent pipe according to claim 1, characterized in that: The foaming agent is azodicarbonamide; The nucleating agent is heavy calcium carbonate or nano calcium carbonate; The foaming regulator is an acrylic acid ester processing aid.

9. A method for preparing the high-impact PVC composite silent pipe according to any one of claims 1 to 8, characterized in that: The preparation method comprises the following steps: S1: Weighing the raw materials of the inner layer (4), the foamed sound insulation layer (3), the hollow sound absorbing layer (2) and the outer layer (1) respectively, and putting the weighed raw materials of the inner layer (4), the foamed sound insulation layer (3), the hollow sound absorbing layer (2) and the outer layer (1) into a high-speed mixing unit for mixing, first hot mixing, then cold mixing, and finally screening and aging to prepare a rigid polyvinyl chloride inner layer mixed material, a foamed sound insulation layer mixed material, a rigid polyvinyl chloride hollow sound absorbing layer mixed material and a modified polyvinyl chloride outer layer mixed material; S2: plasticizing the prepared rigid polyvinyl chloride inner layer mixed material, foamed sound insulation layer mixed material, rigid polyvinyl chloride hollow sound-absorbing layer mixed material and modified polyvinyl chloride outer layer mixed material through a conical twin-screw extruder respectively, and then compounding and molding them in a multi-layer co-extrusion die to prepare a blank; Among them, the barrel temperature of the conical twin-screw extruder is 165-185°C, the temperature of the die body of the multi-layer co-extrusion die is 170-190°C, and the temperature at the outlet of the multi-layer co-extrusion die is 195-208°C; S3: The blank enters a vacuum shaping cooling box and is cooled and shaped by internal pressure and external sizing to produce a high-impact PVC composite silent pipe.

10. The method for preparing a high-impact PVC composite silent pipe according to claim 9, characterized in that: In step S1, during the mixing process of the raw materials of the inner layer (4), the hollow sound-absorbing layer (2) and the outer layer (1) in a high-speed mixing unit, the hot mixing temperature is 120-130° C. and the cold mixing temperature is 45-50° C.; During the mixing process of the raw materials of the foamed sound insulation layer (3) in the high-speed mixing unit, the hot mixing temperature is 110-118° C. and the cold mixing temperature is 40-46° C.

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