A kind of recycled perfluoroether rubber and its processing technology

Abstract

The invention relates to the technical field of rubber and its processing technology, and discloses a regenerated perfluoroether rubber and its processing technology. The invention recovers polymer materials in waste perfluoroether rubber, and adds bio-based or degradable polymer materials, surface-modified nanoparticles, functional polymer additives and environmentally friendly cross-linking agents therein to re-prepare regenerated perfluoroether rubber with excellent performance, thereby reducing environmental pollution, realizing the recycling of resources, effectively coping with the problem of resource waste, and reducing the use cost.

Description

Technical Field

[0001] The invention relates to the technical field of rubber and its processing technology, in particular to a regenerated perfluoroether rubber and its processing technology. Background Art

[0002] Perfluoroether rubber, as a special rubber material with excellent chemical resistance, high and low temperature resistance and high mechanical strength, has demonstrated irreplaceable application value in many high-end fields such as aerospace, automotive industry, petrochemical industry and nuclear industry. This rubber material can still maintain excellent sealing performance in extreme environments, such as high temperature, low temperature, strong acid, strong alkali and other harsh conditions, which is difficult to match with other synthetic rubbers. However, it is precisely because of its unique performance advantages that the production cost of perfluoroether rubber is relatively high, resulting in a relatively expensive use cost.

[0003] At present, there is a general lack of effective recycling mechanisms for the damage of perfluoroether rubber during use. Damaged perfluoroether rubber is often directly discarded or buried, which is not only a huge waste of resources, but also poses a potential pollution risk to the environment because of its special chemical structure, which makes it difficult to degrade in the natural environment. In addition, considering the high cost of perfluoroether rubber, its disposal not only affects economic benefits, but also exacerbates the problem of waste of resources.

[0004] Therefore, how to effectively recycle waste perfluoroether rubber and convert it into materials with reuse value is not only of great significance for reducing environmental pollution and protecting the ecological environment, but also can reduce usage, improve resource utilization efficiency, and achieve a win-win situation of economic and ecological benefits. In this context, a recycled perfluoroether rubber and its processing technology are proposed. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a recycled perfluoroether rubber and a processing technology thereof to solve the background technical problems.

[0006] In the first aspect, in order to achieve the above-mentioned purpose, the present invention provides the following technical solutions: a regenerated perfluoroether rubber, the perfluoroether rubber, calculated by total mass, includes the following mass percentage groups:

[0007] The polymer materials recovered from waste perfluoroether rubber account for 60% to 90% of the total mass;

[0008] Bio-based or degradable polymer materials, selected from polylactic acid (PLA), polyhydroxyalkanoate (PHB) or their copolymers, 5% to 30% of the total mass;

[0009] The surface-modified nanoparticles are selected from graphene oxide, nano-silicon dioxide or a combination thereof, and the amount of the nanoparticles added is 1% to 5% of the total mass;

[0010] A functional polymer additive selected from thermoplastic polyurethane (TPU), polytetrafluoroethylene (PTFE) or modified products thereof, accounting for 1% to 10% of the total mass;

[0011] The environmentally friendly cross-linking agent is selected from isocyanates, peroxides or silane coupling agents, accounting for 0.1% to 2% of the total mass.

[0012] Preferably, the polymer material is recovered from waste perfluoroether rubber by low-temperature closed-loop catalytic cracking technology.

[0013] Preferably, the surface-modified nanoparticles are combined with the polymer material by chemical bonding or physical adsorption.

[0014] Preferably, the average particle size of the nanoparticles is 10 nm to 100 nm.

[0015] Preferably, the surface modifier of the nanoparticles is a silane coupling agent, a titanate coupling agent or a mixture thereof.

[0016] In a second aspect, a processing technology for regenerated perfluoroether rubber is used to prepare the regenerated perfluoroether rubber described in the first aspect, comprising the following steps:

[0017] The waste perfluoroether rubber is sent to a low-temperature closed-loop catalytic cracking unit, where it is cracked using a metal oxide or zeolite catalyst at a temperature of 150°C to 300°C to recover polymer materials;

[0018] Combining the surface-modified nanoparticles with a polymer material by chemical bonding or physical adsorption, and mixing the combined material with a bio-based or degradable polymer material, a functional polymer additive and an environmentally friendly cross-linking agent within the parameter range, and adding the mixed material into a mixing device for blending;

[0019] The blended uniform material is sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles;

[0020] The preliminary regenerated perfluoroether rubber particles are fed into a continuous vulcanization device, and vulcanized at a temperature of 150° C. to 250° C., a pressure of 5 MPa to 20 MPa, and a vulcanization time of 5 minutes to 30 minutes using a microwave or ultrasonic assisted vulcanization process to obtain regenerated perfluoroether rubber.

[0021] Preferably, the recovered polymer material is pretreated, wherein the pretreatment includes removing impurities, adjusting the molecular weight distribution to 50,000 to 500,000 g / mol, and / or improving the surface properties to enhance the compatibility and blending effect with bio-based or degradable polymer materials, nanoparticles, functional polymer additives and environmentally friendly cross-linking agents.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention recovers polymer materials in waste perfluoroether rubber and adds bio-based or degradable polymer materials, surface-modified nanoparticles, functional polymer additives and environmentally friendly cross-linking agents thereto to re-prepare recycled perfluoroether rubber with excellent performance, thereby reducing environmental pollution, achieving the recycling of resources, effectively addressing the problem of resource waste and reducing the cost of use.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and claims. DETAILED DESCRIPTION

[0025] The following will be combined with 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 technical field without creative work are within the scope of protection of the present invention.

[0026] The present invention provides a regenerated perfluoroether rubber and a processing technology thereof, which are used for recycling and reusing waste perfluoroether rubber. Specifically, regenerated perfluoroether rubber with different proportions, materials and processes is prepared through multiple embodiments and multiple comparative examples, and the performance of the prepared regenerated perfluoroether rubber is tested and compared.

[0027] Example 1

[0028] Ratio:

[0029] Polymer materials recovered from waste perfluoroether rubber: 80%

[0030] Bio-based polymer materials (PLA): 15%

[0031] Surface modified nanoparticles (graphene oxide): 3%

[0032] Surface modifier: silane coupling agent

[0033] Average particle size: 50nm

[0034] Functional polymer additives (TPU): 1%

[0035] Environmentally friendly cross-linking agent (isocyanate): 1%

[0036] Processing technology:

[0037] The waste perfluoroether rubber is sent to a low-temperature closed-loop catalytic cracking unit and cracked using a metal oxide catalyst at 200°C to recover polymer materials.

[0038] The recovered polymer material is pre-treated, including removing impurities, adjusting the molecular weight distribution to 100,000 g / mol, and improving the surface properties.

[0039] The graphene oxide nanoparticles were surface modified using a silane coupling agent to ensure that their average particle size was controlled at 50 nm.

[0040] The surface-modified graphene oxide nanoparticles are combined with the pretreated polymer material by chemical bonding.

[0041] The combined material is mixed with PLA, TPU and isocyanate cross-linking agent according to a proportion, and added into a mixing equipment for blending.

[0042] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0043] The primary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 200°C, a pressure of 10 MPa, and a vulcanization time of 15 minutes using a microwave-assisted vulcanization process.

[0044] Example 2

[0045] Ratio:

[0046] Polymer materials recovered from waste perfluoroether rubber: 60%

[0047] Bio-based polymer materials (PLA): 20%

[0048] Surface modified nanoparticles (nanosilica): 5%

[0049] Surface modifier: titanate coupling agent

[0050] Average particle size: 75nm

[0051] Functional polymer additives (TPU): 5%

[0052] Environmentally friendly cross-linking agent (peroxide): 2%

[0053] Processing technology:

[0054] The recovery and pretreatment process of waste perfluoroether rubber is the same as that in Example 1.

[0055] The recovered polymer material is pre-treated, including removing impurities, adjusting the molecular weight distribution to 500,000 g / mol, and improving the surface properties.

[0056] The graphene oxide nanoparticles were surface modified using a silane coupling agent to ensure that their average particle size was controlled at 50 nm.

[0057] The surface-modified nano-silica nanoparticles are combined with the pre-treated polymer material by chemical bonding.

[0058] The combined material is mixed with PLA, TPU and peroxide cross-linking agent according to a proportion, and added into a mixing equipment for blending.

[0059] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0060] The preliminary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 250°C, a pressure of 15 MPa, and a vulcanization time of 5 minutes using a microwave-assisted vulcanization process.

[0061] Example 3

[0062] Ratio:

[0063] Polymer materials recovered from waste perfluoroether rubber: 75%

[0064] Bio-based polymer materials (PLA): 10%

[0065] Surface modified nanoparticles (carbon nanotubes): 10%

[0066] Surface modifier: a mixture of silane coupling agent and titanate coupling agent (ratio 1:1)

[0067] Average particle size: 30nm

[0068] Functional polymer additive (SEBS): 3%

[0069] Environmentally friendly cross-linking agent (peroxide): 2%

[0070] Processing technology:

[0071] The recycling process of waste perfluoroether rubber is the same as that in Example 1.

[0072] The recovered polymer material is pre-treated, including removing impurities, adjusting the molecular weight distribution to 50,000 g / mol, and improving surface properties.

[0073] The carbon nanotubes were surface modified using a mixture of a silane coupling agent and a titanate coupling agent to ensure an average particle size of 30 nm.

[0074] The modified carbon nanotubes are combined with the pretreated polymer material by chemical bonding.

[0075] The combined material is mixed with PLA, SEBS and a peroxide cross-linking agent according to a proportion and blended.

[0076] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0077] The primary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 150°C, a pressure of 5 MPa, and a vulcanization time of 30 minutes using a microwave-assisted vulcanization process.

[0078] Example 4

[0079] Ratio:

[0080] Polymer materials recovered from waste perfluoroether rubber: 85%

[0081] Bio-based polymer materials (PBS): 10%

[0082] Surface modified nanoparticles (nano-alumina): 3%

[0083] Surface modifier: silane coupling agent

[0084] Average particle size: 70nm

[0085] Functional polymer additives (EVA): 2%

[0086] Environmentally friendly cross-linking agent (isocyanate): 2% (including catalyst)

[0087] Processing technology:

[0088] The recycling process of waste perfluoroether rubber is the same as that in Example 1.

[0089] The recovered polymer material is pre-treated, including removing impurities, adjusting the molecular weight distribution to 200,000 g / mol, and improving the surface properties.

[0090] The surface of the nano-alumina was modified using a silane coupling agent to ensure that the average particle size was 70 nm.

[0091] The modified nano-alumina is combined with the pre-treated polymer material by chemical bonding.

[0092] The combined material is mixed with PBS, EVA and an isocyanate cross-linking agent containing a catalyst according to a proportion and blended.

[0093] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0094] The primary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 180°C, a pressure of 10 MPa, and a vulcanization time of 20 minutes using a microwave-assisted vulcanization process.

[0095] Example 5

[0096] Ratio:

[0097] Polymer materials recovered from waste perfluoroether rubber: 65%

[0098] Bio-based polymer materials (PHA): 20%

[0099] Surface modified nanoparticles (a mixture of nano-silica and graphene in a ratio of 1:1): 10%

[0100] Surface modifier: titanate coupling agent

[0101] Average particle size: 50nm (average of the entire mixture)

[0102] Functional polymer additives (TPU): 3%

[0103] Environmentally friendly crosslinking agent (a mixture of peroxides and isocyanates, the ratio is 1:1): 2%

[0104] Processing technology:

[0105] The recycling process of waste perfluoroether rubber is the same as that in Example 1.

[0106] The recovered polymer material is pre-treated, including removing impurities, adjusting the molecular weight distribution to 300,000 g / mol, and improving the surface properties.

[0107] The mixture of nano-silica and graphene was surface modified using a titanate coupling agent to ensure that the overall average particle size was 50 nm.

[0108] The modified mixture is combined with the pretreated polymer material by chemical bonding.

[0109] The combined material is mixed with PHA, TPU and a mixture of peroxides and isocyanates according to a proportion and blended.

[0110] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0111] The primary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 230°C, a pressure of 20 MPa, and a vulcanization time of 10 minutes using a microwave-assisted vulcanization process.

[0112] Comparative Example 1

[0113] Ratio:

[0114] Polymer materials recovered from waste perfluoroether rubber: 40%

[0115] Polyethylene (PE): 40%

[0116] Unmodified nanoparticles (graphene oxide): 10%

[0117] Functional polymer additive (styrene-butadiene-styrene block copolymer, SBS): 5%

[0118] Environmentally friendly cross-linking agent (sulfur): 5%

[0119] Processing technology:

[0120] The recycling process of waste perfluoroether rubber is the same as that in Example 1, but the pretreatment process is simplified and the molecular weight distribution is not adjusted.

[0121] Graphene oxide was used directly without modification.

[0122] The recycled polymer material, PE, unmodified graphene oxide, SBS and sulfur are mixed according to a proportion and blended.

[0123] The blended materials are sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles.

[0124] The primary regenerated perfluoroether rubber particles were fed into a continuous vulcanization device and vulcanized at 100°C, a pressure of 4 MPa, and a vulcanization time of 1 hour using a microwave-assisted vulcanization process.

[0125] Comparative Example 2

[0126] Ratio:

[0127] Polymer materials recovered from waste perfluoroether rubber: 90%

[0128] Functional polymer additives (terpolymer, EPDM): 5%

[0129] Environmentally friendly crosslinking agent (benzoyl peroxide): 5% (without catalyst)

[0130] Processing technology:

[0131] The recycling process of waste perfluoroether rubber is the same as that in Example 1 without pretreatment.

[0132] Without adding nanoparticles, only the recycled polymer material, EPDM and dibenzoyl peroxide without catalyst are mixed in proportion and blended.

[0133] The blended materials are subjected to processes such as granulation and vulcanization to obtain the product.

[0134] The tensile strength, elongation at break and hardness of the recycled perfluoroether rubber prepared in the above-mentioned Examples 1 to 5 and Comparative Examples 1 and 2 were tested using testing equipment. The specific test results are shown in Table 1 below.

[0135] Table 1

[0136]

[0137]

[0138] Based on the comparison of the test results of the embodiment and the comparative example in Table 1, it can be seen that the regenerated perfluoroether rubber and its processing technology proposed in the present invention recycle the waste perfluoroether rubber to prepare a new perfluoroether rubber with excellent performance. The recycled perfluoroether rubber reduces the cost of use and reduces the pollution to the environment, and its performance can still meet the use requirements.

Claims

1. A recycled perfluoroether rubber, characterized in that: Perfluoroether rubber is calculated by total mass and includes the following mass percentage groups: The polymer materials recovered from waste perfluoroether rubber account for 60% to 90% of the total mass; Bio-based or degradable polymer materials, selected from polylactic acid (PLA), polyhydroxyalkanoate (PHB) or their copolymers, 5% to 30% of the total mass; The surface-modified nanoparticles are selected from graphene oxide, nano-silicon dioxide or a combination thereof, and the amount of the nanoparticles added is 1% to 5% of the total mass; A functional polymer additive selected from thermoplastic polyurethane (TPU), polytetrafluoroethylene (PTFE) or modified products thereof, accounting for 1% to 10% of the total mass; The environmentally friendly cross-linking agent is selected from isocyanates, peroxides or silane coupling agents, accounting for 0.1% to 2% of the total mass.

2. A regenerated perfluoroether rubber according to claim 1, characterized in that: The polymer material is recovered from waste perfluoroether rubber by low-temperature closed-loop catalytic cracking technology.

3. The regenerated perfluoroether rubber according to claim 1, characterized in that: The surface-modified nanoparticles are combined with the polymer material by chemical bonding or physical adsorption.

4. The regenerated perfluoroether rubber according to claim 1, characterized in that: The average particle size of the nanoparticles is 10 nm to 100 nm.

5. The regenerated perfluoroether rubber according to claim 1, characterized in that: The surface modifier of the nanoparticles is a silane coupling agent, a titanate coupling agent or a mixture thereof.

6. A processing technology for regenerating perfluoroether rubber, characterized in that: The method for preparing the regenerated perfluoroether rubber according to any one of claims 1 to 5 comprises the following steps: The waste perfluoroether rubber is sent to a low-temperature closed-loop catalytic cracking unit, where it is cracked using a metal oxide or zeolite catalyst at a temperature of 150°C to 300°C to recover polymer materials; Combining the surface-modified nanoparticles with a polymer material by chemical bonding or physical adsorption, and mixing the combined material with a bio-based or degradable polymer material, a functional polymer additive and an environmentally friendly cross-linking agent within the parameter range, and adding the mixed material into a mixing device for blending; The blended uniform material is sent to a granulator for granulation to obtain preliminary regenerated perfluoroether rubber particles; The preliminary regenerated perfluoroether rubber particles are fed into a continuous vulcanization device, and vulcanized at a temperature of 150° C. to 250° C., a pressure of 5 MPa to 20 MPa, and a vulcanization time of 5 minutes to 30 minutes using a microwave or ultrasonic assisted vulcanization process to obtain regenerated perfluoroether rubber.

7. A processing technology for regenerated perfluoroether rubber according to claim 6, characterized in that: The method also includes pre-treating the recycled polymer material, wherein the pre-treatment includes removing impurities, adjusting the molecular weight distribution to 50,000 to 500,000 g / mol, and / or improving the surface properties to enhance the compatibility and blending effect with bio-based or degradable polymer materials, nanoparticles, functional polymer additives and environmentally friendly cross-linking agents.

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