Two-component polyurethane elastic structural adhesive suitable for bonding plastic base material of automobile spoiler and preparation method of two-component polyurethane elastic structural adhesive

Abstract

The invention relates to a two-component polyurethane elastic structural adhesive suitable for bonding a plastic base material of an automobile spoiler. The two-component polyurethane elastic structural adhesive consists of a component A and a component B in a volume ratio of (0.8-1.2): 1, the component A comprises 10-30 parts by weight of liquid polybutadiene polyol; 10 to 30 parts by weight of polyester polyol; 1-10 parts by weight of modified castor oil polyol; 1-10 parts by weight of a chain extender; 20-40 parts by weight of a filler; 1-10 parts by weight of a molecular sieve; 1-5 parts by weight of white carbon black; 0.2 to 2 parts by weight of a tackifier; the component B comprises the following components in parts by weight: 20-40 parts of isocyanate; 20 to 40 parts by weight of liquid polybutadiene polyol; 10-20 parts by weight of a plasticizer; 20-40 parts by weight of a filler; 1-5 parts by weight of white carbon black; 0.2 to 2 parts by weight of an anti-aging agent; 0.2 to 2 parts by weight of a water absorbent; and 0.2 to 2 parts by weight of carbon black. The two-component polyurethane elastic structural adhesive provided by the invention has low hardness and high elongation at break, can realize high adhesive force when SMC / PP and other base materials are only subjected to surface flame treatment, has a bonding failure mode of cohesive failure, and is especially suitable for bonding of automobile spoiler plastic base materials.

Description

Technical Field

[0001] The invention relates to the technical field of adhesives, and more specifically to a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of an automobile spoiler and a preparation method thereof. Background Art

[0002] At present, glue bonding is gradually being used to replace traditional metal riveting in the process of automobile assembly, which brings higher requirements for glue. In the field of automobile rear wings / spoilers, the substrates currently used are composite materials such as SMC / PPGF / PP, which have low surface energy and are difficult to bond. At the same time, since the automobile will cause a certain amount of displacement during high-speed operation, the glue at this application point also needs to have excellent flexibility and aging resistance.

[0003] At present, polyurethane glue usually needs to be primed to deal with low-surface and difficult-to-bond plastic substrates. However, primers are very troublesome in actual use. For example, primers usually contain solvents, which are hazardous chemicals, and the active substances in the primers are prone to failure. Once they fail, they will bring great safety hazards. At present, plastic parts and front and rear windshields have fallen off due to primer failure. In order to meet the customer's requirements for separation of primers and assembly workshops, long-term primers are often required (that is, the effect will not fail within 1 month after the primer is applied), but the technical requirements for long-term primers are higher.

[0004] Considering the incompatibility of the primer, the solution currently proposed by downstream customers is to briefly flame / plasma treat the substrate, usually for 2 to 3 seconds, and then directly apply glue. Flame treatment can slightly increase the surface energy of the substrate, but for substrates such as SMC, due to the high brittleness of the polymer itself, a lot of plasticizers need to be added to improve the toughness of the substrate. A high content of plasticizer is not conducive to the bonding of glue, so even after surface treatment, SMC is still very difficult to bond. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers and a preparation method thereof. The product provided by the present invention has low hardness, high elongation at break, can achieve high adhesion for substrates such as SMC / PP when only surface flame treatment is performed, the bonding failure mode is cohesive failure, the bonding strength reaches 2.5-3.5MPa, and can still ensure excellent adhesion without failure after high temperature and high humidity aging.

[0006] The present invention provides a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of an automobile spoiler, which is composed of a component A and a component B in a volume ratio of (0.8-1.2):1;

[0007] The A component includes:

[0008] 10 to 30 parts by weight of liquid polybutadiene polyol;

[0009] 10 to 30 parts by weight of polyester polyol;

[0010] 1 to 10 parts by weight of modified castor oil polyol;

[0011] 1 to 10 parts by weight of chain extender;

[0012] 20 to 40 parts by weight of filler;

[0013] 1 to 10 parts by weight of molecular sieve;

[0014] 1 to 5 parts by weight of white carbon black;

[0015] 0.2 to 2 parts by weight of tackifier;

[0016] The B component includes:

[0017] 20 to 40 parts by weight of isocyanate;

[0018] 20 to 40 parts by weight of liquid polybutadiene polyol;

[0019] 10 to 20 parts by weight of plasticizer;

[0020] 20 to 40 parts by weight of filler;

[0021] 1 to 5 parts by weight of white carbon black;

[0022] 0.2 to 2 parts by weight of anti-aging agent;

[0023] 0.2 to 2 parts by weight of water absorbent;

[0024] 0.2 to 2 parts by weight of carbon black.

[0025] Preferably, the liquid polybutadiene polyol is selected from one or more of Evonik Polyvest HT, Cray Valley Polybd R45V, and Tianyuan Aviation Materials Tyun HTPBIV;

[0026] The polyester polyol is selected from one or more of Oleon RADIA 7285, Xunjie New Material XJ-56, and Zhejiang Huangma Shangyi New Material HMN-1142T;

[0027] The modified castor oil polyol is selected from ItohOilURIC AC-009 and / or Vertellus Polycin T-400.

[0028] Preferably, the chain extender is selected from 2-ethyl-1,3-hexanediol and / or 2-butyl-2-ethyl-1,3-propanediol.

[0029] Preferably, the tackifier is selected from BYKBYK-4511 and / or ShinEtsuKR-517.

[0030] Preferably, the isocyanate is selected from one or more of diphenylmethane diisocyanate, carbodiimide-uretonimine modified 4,4'-diphenylmethane diisocyanate, BASF aliphatic polyisocyanate Basonat HB 100, and Covestro aliphatic polyisocyanate Desmodur N 100.

[0031] Preferably, the plasticizer is a non-reactive liquid polybutadiene or a hydrocarbon based on naphthalene and biphenyl, with a boiling point above 250°C.

[0032] Preferably, the plasticizer is selected from one or more of Evonik Polyvest 110, Evonik Polyvest 130, and Rutgers Ruetasolv DI.

[0033] The present invention also provides a method for preparing the two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of a car spoiler as described in the above technical solution, comprising the following steps:

[0034] a) heating liquid polybutadiene polyol, polyester polyol, modified castor oil polyol, chain extender, filler and white carbon black to 110° C. to 130° C., mixing and vacuum dehydrating, then cooling to below 50° C., adding molecular sieve and tackifier, and vacuum mixing to obtain component A;

[0035] b) after the isocyanate and the liquid polybutadiene polyol are reacted for the first time, the dried filler, white carbon black, carbon black, the dehydrated plasticizer, the anti-aging agent and the water absorbent are added to carry out a second reaction to obtain component B;

[0036] c) mixing the above-mentioned component A and component B in a volume ratio of (0.8-1.2):1 to obtain a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of a car spoiler;

[0037] There is no restriction on the order of step a) and step b).

[0038] Preferably, the mixing method of heating to 110°C to 130°C in step a) is stirring, and the stirring speed is 400rpm to 600rpm;

[0039] The vacuum degree of the vacuum dehydration is -0.08MPa to -0.1MPa, and the time is 1.5h to 2.5h;

[0040] The vacuum degree of the vacuum mixing is -0.08MPa to -0.1MPa, the rotation speed is 50rpm to 150rpm, and the time is 30min to 60min.

[0041] Preferably, the temperature of the first reaction in step b) is 70°C to 90°C, the speed is 80rpm to 120rpm, the vacuum degree is -0.08MPa to -0.1MPa, and the time is 1.5h to 2.5h;

[0042] The temperature of the second reaction is 10° C. to 40° C., the rotation speed is 180 rpm to 220 rpm, the vacuum degree is -0.08 MPa to -0.1 MPa, and the time is 0.5 h to 1.5 h.

[0043] The invention provides a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of an automobile spoiler, which is composed of a component A and a component B in a volume ratio of (0.8-1.2):1; the component A comprises: 10 to 30 parts by weight of liquid polybutadiene polyol; 10 to 30 parts by weight of polyester polyol; 1 to 10 parts by weight of modified castor oil polyol; 1 to 10 parts by weight of a chain extender; 20 to 40 parts by weight of a filler; and 1 to 1 molecular sieve. 0 parts by weight; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of a tackifier; the B component comprises: 20 to 40 parts by weight of isocyanate; 20 to 40 parts by weight of liquid polybutadiene polyol; 10 to 20 parts by weight of a plasticizer; 20 to 40 parts by weight of a filler; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of an anti-aging agent; 0.2 to 2 parts by weight of a water absorbent; and 0.2 to 2 parts by weight of carbon black. Compared with the prior art, the two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers provided by the present invention adopts specific components with specific contents to achieve better overall interaction. The product has low hardness, high elongation at break, and can achieve high adhesion to substrates such as SMC / PP when only surface flame treatment is performed. The bonding failure mode is cohesive failure, and the bonding strength reaches 2.5-3.5MPa. After high temperature and high humidity aging, it can still ensure excellent adhesion without failure, and is particularly suitable for bonding plastic substrates of automobile spoilers.

[0044] In addition, the preparation method provided by the present invention has simple process, mild conditions, easy control, low requirements on equipment, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1This is a picture after the shear strength test of SMC-PP in Example 1;

[0046] Figure 2 This is a picture of the shear strength test of SMC-PP after high temperature and high humidity aging for 1000 hours in Example 1;

[0047] Figure 3 This is a picture of the shear strength test of SMC-PP after 1000h of hot and cold shock aging in Example 1;

[0048] Figure 4 This is a picture after the shear strength test of SMC-PP in Comparative Example 2. DETAILED DESCRIPTION

[0049] The technical solution of the present invention will be clearly and completely described below in conjunction with 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.

[0050] The present invention provides a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of an automobile spoiler, which is composed of a component A and a component B in a volume ratio of (0.8-1.2):1;

[0051] The A component includes:

[0052] 10 to 30 parts by weight of liquid polybutadiene polyol;

[0053] 10 to 30 parts by weight of polyester polyol;

[0054] 1 to 10 parts by weight of modified castor oil polyol;

[0055] 1 to 10 parts by weight of chain extender;

[0056] 20 to 40 parts by weight of filler;

[0057] 1 to 10 parts by weight of molecular sieve;

[0058] 1 to 5 parts by weight of white carbon black;

[0059] 0.2 to 2 parts by weight of tackifier;

[0060] The B component includes:

[0061] 20 to 40 parts by weight of isocyanate;

[0062] 20 to 40 parts by weight of liquid polybutadiene polyol;

[0063] 10 to 20 parts by weight of plasticizer;

[0064] 20 to 40 parts by weight of filler;

[0065] 1 to 5 parts by weight of white carbon black;

[0066] 0.2 to 2 parts by weight of anti-aging agent;

[0067] 0.2 to 2 parts by weight of water absorbent;

[0068] 0.2 to 2 parts by weight of carbon black.

[0069] The present invention provides a two-component polyurethane elastic structural adhesive suitable for bonding of automobile spoiler plastic substrates, which solves the problem that the existing adhesive products have poor bonding performance for automobile spoiler composite materials and cannot meet the actual use conditions of customers; the present invention mainly starts with the selection of polyurethane resin, because the substrate to be bonded by the present invention is mainly a plastic substrate such as SMC / PP, first clarify the molecular structure of the substrate itself, mainly polypropylene, polyethylene, unsaturated polyester resin, etc. On this basis, when selecting polyurethane resin, it is necessary to introduce as many polyolefin / unsaturated polyester segments as possible, relying on the similar and compatible characteristics of resins, and improve the compatibility of polyurethane glue for plastic substrates, so as to achieve the purpose of improving adhesion; on the other hand, since the present invention also needs to reduce the hardness of glue and improve the elongation at break of glue, the selection of plasticizer is also crucial. Finally, the present invention realizes efficient bonding for plastic substrates such as SMC-PP through reasonable formula design, and the flexibility of the glue itself is excellent.

[0070] In the present invention, the two-component polyurethane elastic structural adhesive suitable for bonding the plastic substrate of the automobile spoiler is composed of component A and component B in a volume ratio of (0.8-1.2):1, preferably 1:1.

[0071] In the present invention, the A component comprises:

[0072] 10 to 30 parts by weight of liquid polybutadiene polyol;

[0073] 10 to 30 parts by weight of polyester polyol;

[0074] 1 to 10 parts by weight of modified castor oil polyol;

[0075] 1 to 10 parts by weight of chain extender;

[0076] 20 to 40 parts by weight of filler;

[0077] 1 to 10 parts by weight of molecular sieve;

[0078] 1 to 5 parts by weight of white carbon black;

[0079] 0.2 to 2 parts by weight of tackifier;

[0080] It is preferably prepared from the following raw materials:

[0081] 24 to 27 parts by weight of liquid polybutadiene polyol;

[0082] 24 to 26 parts by weight of polyester polyol;

[0083] 2 to 7 parts by weight of modified castor oil polyol;

[0084] 4 to 5 parts by weight of chain extender;

[0085] 34 to 35 parts by weight of filler;

[0086] 3 to 5 parts by weight of molecular sieve;

[0087] 1 to 2 parts by weight of white carbon black;

[0088] Thickener 0.5 to 1.5 parts by weight.

[0089] In the present invention, the liquid polybutadiene polyol is preferably selected from one or more of Evonik Polyvest HT, Cray Valley Poly bd R45V, and Tianyuan Aviation Materials Tyun HTPBIV, and more preferably Evonik Polyvest HT, Cray Valley Poly bd R45V, or Tianyuan Aviation Materials Tyun HTPBIV. The present invention has no particular restrictions on the source of the liquid polybutadiene polyol, and commercially available products well known to those skilled in the art can be used.

[0090] In the present invention, the polyester polyol is preferably selected from one or more of Oleon RADIA 7285, Xunjie New Material XJ-56, and Zhejiang Huangma Shangyi New Material HMN-1142T, and more preferably one or two of Oleon RADIA 7285 and Xunjie New Material XJ-56. The present invention has no particular limitation on the source of the polyester polyol, and commercially available products known to those skilled in the art can be used.

[0091] In the present invention, the modified castor oil polyol is preferably selected from Itoh Oil URIC AC-009 and / or Vertellus Polycin T-400, more preferably Itoh Oil URIC AC-009 or Vertellus Polycin T-400. The present invention has no particular limitation on the source of the modified castor oil polyol, and commercially available products known to those skilled in the art can be used.

[0092] In the present invention, the chain extender is preferably selected from 2-ethyl-1,3-hexanediol and / or 2-butyl-2-ethyl-1,3-propanediol, more preferably 2-ethyl-1,3-hexanediol or 2-butyl-2-ethyl-1,3-propanediol. The present invention has no particular limitation on the source of the chain extender, and commercially available products known to those skilled in the art can be used.

[0093] In the present invention, the filler is preferably selected from Omya Omyacarb 2T-JI and / or Omya Omyacarb 5T-JI, more preferably Omya Omyacarb 2T-JI or Omya Omyacarb 5T-JI; the molecular sieve is preferably GraceSylosiv A 300; the white carbon black is preferably selected from CABOT CAB-O-SIL TS-720 and / or Evonik AEROSILR202, more preferably CABOT CAB-O-SIL TS-720 or Evonik AEROSIL R202. The present invention has no particular restrictions on the sources of the filler, molecular sieve and white carbon black, and commercial products well known to those skilled in the art can be used.

[0094] In the present invention, the tackifier is preferably selected from BYK BYK-4511 and / or ShinEtsu KR-517, more preferably BYK BYK-4511 or ShinEtsu KR-517. The present invention has no particular limitation on the source of the tackifier, and commercially available products known to those skilled in the art may be used.

[0095] In the present invention, the B component comprises:

[0096] 20 to 40 parts by weight of isocyanate;

[0097] 20 to 40 parts by weight of liquid polybutadiene polyol;

[0098] 10 to 20 parts by weight of plasticizer;

[0099] 20 to 40 parts by weight of filler;

[0100] 1 to 5 parts by weight of white carbon black;

[0101] 0.2 to 2 parts by weight of anti-aging agent;

[0102] 0.2 to 2 parts by weight of water absorbent;

[0103] 0.2 to 2 parts by weight of carbon black;

[0104] It is preferably prepared from the following raw materials:

[0105] 24 to 26 parts by weight of isocyanate;

[0106] 21 to 26 parts by weight of liquid polybutadiene polyol;

[0107] 10 to 15 parts by weight of plasticizer;

[0108] 30 to 35 parts by weight of filler;

[0109] 1 to 2 parts by weight of white carbon black;

[0110] 0.5 to 1.5 parts by weight of an anti-aging agent;

[0111] 0.4 to 0.6 parts by weight of water absorbent;

[0112] 0.4 to 0.6 parts by weight of carbon black.

[0113] In the present invention, the liquid polybutadiene polyol, filler and white carbon black are the same as those in the above-mentioned component A, and are not described in detail herein.

[0114] In the present invention, the isocyanate is preferably selected from one or more of diphenylmethane diisocyanate, carbodiimide-uretonimine modified 4,4'-diphenylmethane diisocyanate, BASF aliphatic polyisocyanate Basonat HB 100, and Covestro aliphatic polyisocyanate Desmodur N 100, and more preferably two of Wanhua diphenylmethane diisocyanate (MDI-100), Wanhua carbodiimide-uretonimine modified 4,4'-diphenylmethane diisocyanate (CDMDI-100L), BASF aliphatic polyisocyanate (HDI biuret) Basonat HB 100, and Covestro aliphatic polyisocyanate (HDI biuret) Desmodur N 100. The present invention has no particular restrictions on the source of the isocyanate, and commercially available products known to those skilled in the art can be used.

[0115] In the present invention, the plasticizer is preferably a non-reactive liquid polybutadiene or a hydrocarbon based on naphthalene and biphenyl, and the boiling point is preferably higher than 250°C.

[0116] In a preferred embodiment of the present invention, the plasticizer is selected from one or more of Evonik Polyvest 110, Evonik Polyvest 130, and Rutgers Ruetasolv DI, preferably Evonik Polyvest 110, Evonik Polyvest 130, or Rutgers Ruetasolv DI. The present invention has no particular limitation on the source of the plasticizer, and commercially available products known to those skilled in the art may be used.

[0117] In the present invention, the anti-aging agent is preferably Taiwan Double Bond Chinox TP-10H; the water absorbent is preferably Borchers TI; the carbon black is preferably Hangzhou HZ6004; all of them are commercially available products well known to those skilled in the art, and the present invention has no special limitation on their sources.

[0118] The formula design idea of ​​the present invention is as follows: liquid polybutadiene polyol and polyester polyol are used as main resins in the polyol component to improve the compatibility and adhesion of the glue to the plastic substrate; modified castor oil polyol and chain extender are used to improve the rigidity of the chain segment and improve the strength of the glue itself; tackifier is used to further improve the adhesion of the glue to the plastic substrate; at the same time, liquid polybutadiene is introduced into the chain segment of the isocyanate prepolymer in the form of a prepolymer in the isocyanate component to further improve the compatibility of the glue to the plastic substrate; special plasticizer is used to reduce the hardness of the system and improve the elongation at break of the system.

[0119] On this basis, the two-component polyurethane elastic structural adhesive provided by the present invention adopts specific components with specific contents to achieve better overall interaction. The product has low hardness and high elongation at break. For plastic substrates such as SMC / PP, when the surface is treated with flame for only 2 to 3 seconds, 100% cohesive failure can be achieved, and the shear strength can reach 2.5 to 3.5 MPa; after aging at high temperature and high humidity for 1000 hours, 100% cohesive failure is still achieved, and the shear strength is almost not attenuated; the hardness of the glue itself is low, at 55 to 65 Shore-A, and the elongation at break is greater than 350%.

[0120] The present invention also provides a method for preparing the two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of a car spoiler as described in the above technical solution, comprising the following steps:

[0121] a) heating liquid polybutadiene polyol, polyester polyol, modified castor oil polyol, chain extender, filler and white carbon black to 110° C. to 130° C., mixing and vacuum dehydrating, then cooling to below 50° C., adding molecular sieve and tackifier, and vacuum mixing to obtain component A;

[0122] b) after the isocyanate and the liquid polybutadiene polyol are reacted for the first time, the dried filler, white carbon black, carbon black, the dehydrated plasticizer, the anti-aging agent and the water absorbent are added to carry out a second reaction to obtain component B;

[0123] c) mixing the above-mentioned component A and component B in a volume ratio of (0.8-1.2):1 to obtain a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of a car spoiler;

[0124] There is no restriction on the order of step a) and step b).

[0125] In the present invention, the raw materials are the same as those described in the above technical solution and will not be described in detail here.

[0126] In the present invention, the mixing method of heating to 110°C to 130°C in step a) is preferably stirring, and the stirring speed is preferably 400rpm to 600rpm, more preferably 500rpm; the vacuum degree of the vacuum dehydration is preferably -0.08MPa to -0.1MPa, and the time is preferably 1.5h to 2.5h; the vacuum degree of the vacuum mixing is preferably -0.08MPa to -0.1MPa, the rotation speed is preferably 50rpm to 150rpm, more preferably 100rpm, and the time is preferably 30min to 60min.

[0127] In the present invention, the temperature of the first reaction in step b) is preferably 70°C to 90°C, more preferably 80°C, the rotation speed is preferably 80rpm to 120rpm, more preferably 100rpm, the vacuum degree is preferably -0.08MPa to -0.1MPa, and the time is preferably 1.5h to 2.5h; the temperature of the second reaction is preferably 10°C to 40°C, more preferably 20°C to 30°C, the rotation speed is preferably 180rpm to 220rpm, more preferably 200rpm, the vacuum degree is preferably -0.08MPa to -0.1MPa, and the time is preferably 0.5h to 1.5h.

[0128] In the present invention, the drying process in step b) is preferably specifically as follows:

[0129] The filler, white carbon black and carbon black are dried and dehydrated in a drying room at 90° C. to 110° C. for 45 h to 50 h to obtain dried filler, white carbon black and carbon black.

[0130] In the present invention, the dehydration process in step b) is preferably specifically as follows:

[0131] The plasticizer is dehydrated at 110° C. to 130° C. under vacuum to -0.08 MPa to -0.1 MPa for 1.5 h to 2.5 h to obtain a dehydrated plasticizer.

[0132] The preparation method provided by the invention has simple process, mild conditions, easy control, low requirements on equipment, and has broad application prospects.

[0133] The invention provides a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of an automobile spoiler, which is composed of a component A and a component B in a volume ratio of (0.8-1.2):1; the component A comprises: 10 to 30 parts by weight of liquid polybutadiene polyol; 10 to 30 parts by weight of polyester polyol; 1 to 10 parts by weight of modified castor oil polyol; 1 to 10 parts by weight of a chain extender; 20 to 40 parts by weight of a filler; and 1 to 1 molecular sieve. 0 parts by weight; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of a tackifier; the B component comprises: 20 to 40 parts by weight of isocyanate; 20 to 40 parts by weight of liquid polybutadiene polyol; 10 to 20 parts by weight of a plasticizer; 20 to 40 parts by weight of a filler; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of an anti-aging agent; 0.2 to 2 parts by weight of a water absorbent; and 0.2 to 2 parts by weight of carbon black. Compared with the prior art, the two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers provided by the present invention adopts specific components with specific contents to achieve better overall interaction. The product has low hardness, high elongation at break, and can achieve high adhesion to substrates such as SMC / PP when only surface flame treatment is performed. The bonding failure mode is cohesive failure, and the bonding strength reaches 2.5-3.5MPa. After high temperature and high humidity aging, it can still ensure excellent adhesion without failure, and is particularly suitable for bonding plastic substrates of automobile spoilers.

[0134] In addition, the preparation method provided by the present invention has simple process, mild conditions, easy control, low requirements on equipment, and has broad application prospects.

[0135] In order to further illustrate the present invention, the following examples are provided for detailed description. The raw materials involved in the following examples of the present invention are as follows:

[0136] Liquid polybutadiene polyols: Evonik Polyvest HT, Cray Valley Poly bd R45V, Tianyuan Aviation Materials Tyun HTPBIV;

[0137] Polyester polyols: Oleon RADIA 7285, Xunjie New Materials XJ-56, Zhejiang Huangma Shangyi New Materials Co., Ltd. HMN-1142T;

[0138] Modified castor oil polyols: Itoh OilURIC AC-009, Vertellus Polycin T-400;

[0139] Chain extenders: 2-ethyl-1,3-hexanediol (EHD), 2-butyl-2-ethyl-1,3-propanediol (BEPD);

[0140] Isocyanate: Wanhua diphenylmethane diisocyanate (MDI-100), Wanhua carbodiimide-uretonimine modified 4,4'-diphenylmethane diisocyanate (CDMDI-100L), BASF aliphatic polyisocyanate (HDI biuret) Basonat HB 100, Covestro aliphatic polyisocyanate (HDI biuret) Desmodur N 100;

[0141] Plasticizer: non-reactive liquid polybutadiene or hydrocarbons based on naphthalene and biphenyl with a boiling point above 250°C, including: Evonik Polyvest 110, Evonik Polyvest 130, Rutgers Ruetasolv DI;

[0142] Filler: Omya Omyacarb 2T-JI, Omya Omyacarb 5T-JI;

[0143] Molecular sieve: Grace Sylosiv A 300;

[0144] White carbon black: CABOT CAB-O-SIL TS-720, Evonik AEROSIL R202;

[0145] Tackifier: BYK BYK-4511, ShinEtsu KR-517;

[0146] Anti-aging agent: Taiwan Double Bond Chinox TP-10H;

[0147] Water absorbent: Borchers TI;

[0148] Carbon black: Hangzhou HZ6004.

[0149] Example 1

[0150] Component A: 25 parts by weight of Polyvest HT liquid polybutadiene, 25 parts by weight of Oleon RADIA 7285 polyester polyol, 5 parts by weight of Polycin T-400 modified castor oil polyol, 4 parts by weight of EHD chain extender, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of AEROSIL R202 white carbon black, and 1 part by weight of BYK-4511 tackifier.

[0151] Component B: 20 ​​parts by weight of CDMDI-100L isocyanate, 6 parts by weight of Basonat HB 100 isocyanate, 26 parts by weight of Polyvest HT liquid polybutadiene, 10 parts by weight of Polyvest 110 plasticizer, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 1 part by weight of AEROSIL R202 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0152] Example 2

[0153] Component A: 24 parts by weight of Poly bd R45V liquid polybutadiene polyol, 24 parts by weight of XJ-56 polyester polyol, 7 parts by weight of URIC AC-009 modified castor oil polyol, 5 parts by weight of EHD chain extender, 34 parts by weight of Omyacarb 5T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of CAB-O-SIL TS-720 white carbon black, and 1 part by weight of KR-517 tackifier.

[0154] Component B: 16 parts by weight of MDI-100 isocyanate, 10 parts by weight of Desmodur N 100 isocyanate, 21 parts by weight of Poly bdR45V liquid polybutadiene polyol, 15 parts by weight of Ruetasolv DI plasticizer, 35 parts by weight of Omyacarb 5T-JI calcium carbonate, 1 part by weight of CAB-O-SIL TS-720 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0155] Example 3

[0156] Component A: 27 parts by weight of Tyun HTPBIV liquid polybutadiene polyol, 16 parts by weight of RADIA 7285 polyester polyol, 10 parts by weight of HMN-1142T polyester polyol, 2 parts by weight of URIC AC-009 modified castor oil polyol, 4 parts by weight of BEPD chain extender, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of CAB-O-SILTS-720 white carbon black, and 1 part by weight of KR-517 tackifier.

[0157] Component B: 20 ​​parts by weight of CDMDI-100L isocyanate, 4 parts by weight of Desmodur N 100 isocyanate, 24 parts by weight of TyunHTPBIV liquid polybutadiene polyol, 15 parts by weight of Polyvest 130 plasticizer, 1 part by weight of CAB-O-SIL TS-720 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0158] Comparative Example 1

[0159] Component A: 50 parts by weight of Polyvest HT liquid polybutadiene, 5 parts by weight of Polycin T-400 modified castor oil polyol, 4 parts by weight of EHD chain extender, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of AEROSIL R202 white carbon black, and 1 part by weight of BYK-4511 tackifier.

[0160] Component B: 20 ​​parts by weight of CDMDI-100L isocyanate, 6 parts by weight of Basonat HB 100 isocyanate, 26 parts by weight of Polyvest HT liquid polybutadiene, 10 parts by weight of Polyvest 110 plasticizer, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 1 part by weight of AEROSIL R202 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0161] Comparative Example 2

[0162] Component A: 50 parts by weight of XJ-56 polyester polyol, 5 parts by weight of Polycin T-400 modified castor oil polyol, 4 parts by weight of EHD chain extender, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of AEROSIL R202 white carbon black, and 1 part by weight of BYK-4511 tackifier.

[0163] Component B: 20 ​​parts by weight of CDMDI-100L isocyanate, 6 parts by weight of Basonat HB 100 isocyanate, 26 parts by weight of Polyvest HT liquid polybutadiene, 10 parts by weight of Polyvest 110 plasticizer, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 1 part by weight of AEROSIL R202 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0164] Comparative Example 3

[0165] Component A: 25 parts by weight of Polyvest HT liquid polybutadiene, 25 parts by weight of Oleon RADIA 7285 polyester polyol, 5 parts by weight of Polycin T-400 modified castor oil polyol, 4 parts by weight of EHD chain extender, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 4 parts by weight of Sylosiv A 300 molecular sieve, 1 part by weight of AEROSIL R202 white carbon black, and 1 part by weight of BYK-4511 tackifier.

[0166] Component B: 25 parts by weight of CDMDI-100L isocyanate, 6 parts by weight of Basonat HB 100 isocyanate, 31 parts by weight of Polyvest HT liquid polybutadiene, 35 parts by weight of Omyacarb 2T-JI calcium carbonate, 1 part by weight of AEROSIL R202 white carbon black, 1 part by weight of Chinox TP-10H antioxidant, 0.5 parts by weight of TI water absorbent, and 0.5 parts by weight of HZ6004 carbon black.

[0167] The above formula is shown in Table 1 below.

[0168] Table 1

[0169]

[0170] The specific preparation methods of the two-component polyurethane elastic structural adhesive provided in the above embodiments and comparative examples are as follows:

[0171] Component A:

[0172] Liquid polybutadiene polyol, polyester polyol, modified castor oil polyol, chain extender, filler, and white carbon black thixotropic agent were heated to 120°C with stirring at 500 rpm, evacuated to -0.09 MPa, and dehydrated for 2 hours. Then the temperature was lowered to below 50°C, molecular sieves and tackifiers were added, the pressure was evacuated to below -0.09 MPa, and stirring was continued at 100 rpm for 45 minutes to obtain component A.

[0173] Component B:

[0174] First, the filler, white carbon black and carbon black are dried and dehydrated in a drying room at 100°C for 48 hours for use;

[0175] The plasticizer was vacuumed to -0.09 MPa at 120°C and dehydrated for 2 h for later use;

[0176] Isocyanate and liquid polybutadiene polyol were stirred at 100 rpm at 80°C and evacuated to -0.09 MPa for reaction for 2 hours, and then the pre-dried filler, white carbon black, and carbon black were added, and the pre-dehydrated plasticizer was added. Anti-aging agent and water absorbent were added, and the mixture was stirred at 200 rpm at room temperature and evacuated to -0.09 MPa for reaction for 1 hour to obtain component B.

[0177] The above-mentioned component A and component B are evenly mixed in a volume ratio of 1:1 to obtain a two-component polyurethane elastic structural adhesive.

[0178] Comparative Example 4

[0179] Competitor 1: PPG / TOTALSEAL 6023, commercially available.

[0180] Comparative Example 5

[0181] Competitor 2: HB Fuller / TONSAN TS856, commercially available.

[0182] The various properties of the two-component polyurethane elastic structural adhesive provided in each embodiment and comparative example were tested, and the test standards are as follows:

[0183] Hardness: GB / T 531.1-2008, Standard for the test method of indentation hardness of vulcanized rubber or thermoplastic rubber;

[0184] Shear strength: GB / T 7124-2008, Determination of tensile shear strength of adhesives (rigid material to rigid material);

[0185] Body strength: GB / T 528-2009, Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber;

[0186] Elongation at break: GB / T 528-2009, Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber;

[0187] High temperature and high humidity aging: GB / T 2423.50-2012, Environmental testing for electrical and electronic products Part 2: Test methods Steady humidity and heat is mainly used for accelerated testing of components;

[0188] Thermal shock aging: GB / T 2423.102-2008, Environmental testing for electric and electronic products Part 2: Test method Test: Temperature (low temperature, high temperature) / low pressure / vibration (sinusoidal) combined.

[0189] The test results are shown in Table 2 and Figures 1 to 4 As shown; among them, Figure 1 This is a picture of the SMC-PP shear strength test in Example 1. It can be seen that the failure mode is 100% cohesive failure; Figure 2In Example 1, after aging at high temperature and high humidity for 1000 hours, the SMC-PP shear strength test is shown. It can be seen that the failure mode is 100% cohesive failure or PP substrate fracture. This is because the strength of the PP substrate is reduced due to aging. Figure 3 In Example 1, after 1000h of hot and cold shock aging, the SMC-PP shear strength test is shown. It can be seen that the failure mode is 100% cohesive failure or PP substrate fracture. This is because the strength of the PP substrate is reduced due to aging. Figure 4 This is a picture of the SMC-PP shear strength test in Comparative Example 2. It can be seen that the failure mode is interface damage.

[0190] Table 2

[0191]

[0192]

[0193] Experimental results show that the two-component polyurethane elastic structural adhesive provided by the present invention can adjust the hardness and bulk strength of the adhesive itself by controlling the amount of modified castor oil and chain extender, can control the strength and elongation at break of the adhesive itself by controlling the feed ratio of isocyanate to polyol in the prepolymer, and can adjust the hardness and elongation at break of the adhesive by controlling the amount of plasticizer added. From the comparative experiments, if we rely solely on liquid polybutadiene polyol as the resin, the adhesion and compatibility with the plastic substrate are good, but the overall strength of the glue is low, and the final fracture stress is low, which cannot meet the customer's requirements for strength values; if we rely solely on amorphous polyester polyol as the resin, the overall strength will be significantly improved, but the compatibility with low-polarity / low-surface-energy plastic substrates will decrease, and 100% cohesive failure cannot be achieved; if no plasticizer is added to the system, the flexibility / elongation at break of the glue will be significantly reduced, which cannot meet the customer's requirements for the glue's anti-displacement ability. At the same time, since no plasticizer is added, the strength of the system will also increase, and there is a probability that the glue cohesive strength will be greater than the bonding strength between the glue and the substrate, resulting in interface peeling. Compared with two competitive products recognized by the market, the solution in the present invention is comparable in terms of body strength, interface failure, etc., while the glue is more flexible, and has higher adhesion and shear strength to the substrate; and the entire formula system is very excellent in terms of adhesion to plastic SMC / PP substrates, which can basically achieve 100% cohesive failure, and the strength is not less than 2.5MPa; it has excellent aging resistance.

[0194] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers, consisting of component A and component B in a volume ratio of (0.8-1.2):1; The A component comprises: 10 to 30 parts by weight of liquid polybutadiene polyol; 10 to 30 parts by weight of polyester polyol; 1 to 10 parts by weight of modified castor oil polyol; 1 to 10 parts by weight of chain extender; 20 to 40 parts by weight of filler; 1 to 10 parts by weight of molecular sieve; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of tackifier; The B component includes: 20 to 40 parts by weight of isocyanate; 20 to 40 parts by weight of liquid polybutadiene polyol; 10 to 20 parts by weight of plasticizer; 20 to 40 parts by weight of filler; 1 to 5 parts by weight of white carbon black; 0.2 to 2 parts by weight of anti-aging agent; 0.2 to 2 parts by weight of water absorbent; 0.2 to 2 parts by weight of carbon black.

2. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 1, characterized in that: The liquid polybutadiene polyol is selected from one or more of Evonik PolyvestHT, Cray Valley Poly bdR45V, and Tianyuan Aviation Materials Tyun HTPBIV; The polyester polyol is selected from one or more of Oleon RADIA 7285, Xunjie New Material XJ-56, and Zhejiang Huangma Shangyi New Material HMN-1142T; The modified castor oil polyol is selected from Itoh OilURIC AC-009 and / or Vertellus Polycin T-400.

3. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 1, characterized in that: The chain extender is selected from 2-ethyl-1,3-hexanediol and / or 2-butyl-2-ethyl-1,3-propanediol.

4. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 1, characterized in that: The tackifier is selected from BYKBYK-4511 and / or ShinEtsu KR-517.

5. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 1, characterized in that: The isocyanate is selected from one or more of diphenylmethane diisocyanate, carbodiimide-uretonimine modified 4,4'-diphenylmethane diisocyanate, BASF aliphatic polyisocyanate Basonat HB 100, and Covestro aliphatic polyisocyanate Desmodur N 100.

6. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 1, characterized in that: The plasticizer is a non-reactive liquid polybutadiene or a hydrocarbon based on naphthalene and biphenyl with a boiling point above 250°C.

7. The two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to claim 6, characterized in that: The plasticizer is selected from one or more of Evonik Polyvest 110, Evonik Polyvest 130, and Rutgers Ruetasolv DI.

8. A method for preparing the two-component polyurethane elastic structural adhesive suitable for bonding plastic substrates of automobile spoilers according to any one of claims 1 to 7, comprising the following steps: a) heating liquid polybutadiene polyol, polyester polyol, modified castor oil polyol, chain extender, filler and white carbon black to 110° C. to 130° C., mixing and vacuum dehydrating, then cooling to below 50° C., adding molecular sieve and tackifier, and vacuum mixing to obtain component A; b) after the isocyanate and the liquid polybutadiene polyol are reacted for the first time, the dried filler, white carbon black, carbon black, the dehydrated plasticizer, the anti-aging agent and the water absorbent are added to carry out a second reaction to obtain component B; c) mixing the above-mentioned component A and component B in a volume ratio of (0.8-1.2):1 to obtain a two-component polyurethane elastic structural adhesive suitable for bonding a plastic substrate of a car spoiler; There is no restriction on the order of step a) and step b).

9. The preparation method according to claim 8, characterized in that: The mixing method of heating to 110° C. to 130° C. in step a) is stirring, and the stirring speed is 400 rpm to 600 rpm; The vacuum degree of the vacuum dehydration is -0.08MPa to -0.1MPa, and the time is 1.5h to 2.5h; The vacuum degree of the vacuum mixing is -0.08MPa to -0.1MPa, the rotation speed is 50rpm to 150rpm, and the time is 30min to 60min.

10. The preparation method according to claim 8, characterized in that: The temperature of the first reaction in step b) is 70°C to 90°C, the speed is 80rpm to 120rpm, the vacuum degree is -0.08MPa to -0.1MPa, and the time is 1.5h to 2.5h; The temperature of the second reaction is 10° C. to 40° C., the rotation speed is 180 rpm to 220 rpm, the vacuum degree is -0.08 MPa to -0.1 MPa, and the time is 0.5 h to 1.5 h.

Images