ASA (acrylonitrile styrene acrylate) material capable of being bonded with PVC (polyvinyl chloride) without prime coat and preparation method of ASA material

Abstract

The invention discloses an ASA material capable of being bonded with PVC without a base coat and a preparation method of the ASA material, and the ASA material capable of being bonded with PVC without the base coat is obtained by mixing SAN resin, ASA rubber powder, filler, ACR and auxiliaries. In the prior art, PVC and an insert are bonded in a glue prime coat mode, so that the process is long, the cost is high, VOC volatilization exists, and the environment is not protected; the glue prime coat mode increases one procedure, so that the efficiency is low, and the time is consumed; the invention develops the modified ASA material which is a low-cost prime coat-free modified ASA material capable of being bonded with PVC, the problem of prime coat-free bonding is solved, the cost is greatly reduced, and the modified ASA material is extremely environment-friendly.

Description

Technical Field

[0001] This invention pertains to material modification technology and relates to a modified ASA material, specifically an ASA material that can be bonded to PVC without a primer and its preparation method. Background Technology

[0002] Currently, most automotive glass seals utilize elastic edge-molding. Areas without glass support typically use PP+GF material or nylon with glass fiber reinforcement as inserts, surrounded by PVC material. This static seal is used for dustproofing, waterproofing, and sound insulation. The current problem is that both of these materials have poor compatibility with soft PVC, requiring a primer to improve adhesion between the soft and hard adhesives. Existing technology discloses a glass edge-molding assembly and its injection molding method. A primer is applied to the surface of a PMMA plastic trim panel to be injection molded. The gate of the injection molding cavity is aligned with the inner surface of the plastic trim panel. Plasticized thermoplastic resin is injected into the injection molding cavity through the gate, and the glass edge-molding assembly is obtained after cooling and solidification. Existing technology also discloses a wear-resistant and sound-absorbing coating process for PVC side window triangular edge-molding products, where a primer is applied to the substrate to ensure coating adhesion. However, the introduction of a primer (adhesive) increases the product molding process, raises costs, and increases VOC emissions from automotive parts. In addition, current applications (automobile manufacturers) require that no voids appear after edge-sealing injection molding, which is difficult for existing products to meet. Summary of the Invention

[0003] In existing technologies, bonding PVC to inserts uses an adhesive primer, which is a long and costly process with VOC emissions, making it environmentally unfriendly. Moreover, the adhesive primer method adds an extra step, resulting in low efficiency and time consumption. This invention develops a modified ASA material, which is a low-cost modified ASA material that can bond to PVC without a primer, solving the problem of primer-free bonding, greatly reducing costs, and is also highly environmentally friendly.

[0004] The present invention adopts the following technical solution.

[0005] A primerless ASA material for bonding with PVC includes SAN resin, ASA adhesive powder, filler, ACR, and additives.

[0006] In this invention, the filler includes calcium carbonate.

[0007] In this invention, ACR is an existing product, specifically an acrylate copolymer.

[0008] In this invention, the additives include one or more of the following: processing aids and pigments.

[0009] In this invention, the processing aids are antioxidants and lubricants, which can improve the processing performance and weather resistance of the product; the pigment is added according to the product application requirements and can be a carbon black colorant. The prepared modified ASA material is black, that is, black soft PVC edge-wrapping ASA material without primer.

[0010] In this invention, the weight ratio of SAN resin, ASA adhesive powder, filler, ACR, and additives is (15-40):(30-50):(10-20):(15-40):(1-4).

[0011] Preferably, the weight ratio of SAN resin, ASA adhesive powder, filler, ACR and additives is (20-30): (30-40): (10-20): (20-30): (1-4).

[0012] More preferably, the weight ratio of SAN resin, ASA adhesive powder, filler, ACR and additives is (20-30): (33-37): (12-20): (20-30): (2-3).

[0013] More preferably, the weight ratio of SAN resin, ASA adhesive powder, filler, ACR and additives is (22-27): (33-37): (12-17): (23-28): (2-3).

[0014] In this invention, the ASA material for bonding with PVC without primer is prepared from SAN resin, ASA adhesive powder, filler, ACR, and additives.

[0015] This invention discloses a method for preparing the above-mentioned ASA material that can be bonded to PVC without primer, wherein SAN resin, ASA adhesive powder, filler, ACR and additives are mixed to obtain the ASA material that can be bonded to PVC without primer.

[0016] In this invention, the mixing is melt mixing; furthermore, an extruder is used to achieve melt mixing.

[0017] This invention discloses an edge-sealing material, comprising the above-mentioned ASA material for bonding with PVC without primer and PVC.

[0018] Furthermore, among the aforementioned edging materials, PVC wrapping and PVC-based ASA adhesive without primer are used.

[0019] Furthermore, there is no adhesive layer between the ASA material and the PVC (no primer required for bonding). As is common knowledge, the adhesive layer here refers to any other reagent besides the ASA material and PVC used for bonding.

[0020] This invention discloses a method for preparing the above-mentioned edge-sealing material, which uses ASA material that is bonded to PVC without primer as an insert and PVC as the edge-sealing material for edge-sealing injection molding to obtain the edge-sealing material.

[0021] Furthermore, no primer is required during edge-sealing injection molding. This invention solves the technical problem that existing edge-sealing materials require primer to achieve bonding between the insert and PVC. It discloses for the first time a modified ASA material as an insert that achieves excellent bonding with PVC without the need for a primer, which is unexpected.

[0022] This invention discloses an automotive material, including the above-mentioned ASA material or edge-binding material that is bonded to PVC without primer.

[0023] This invention discloses the application of the above-mentioned ASA material or edge-binding material that is bonded to PVC without primer in the preparation or as an automotive material.

[0024] This invention discloses the application of the above-mentioned ASA material for bonding with PVC without primer in the preparation of edge-sealing materials.

[0025] This invention discloses the application of the above-mentioned ASA material for bonding with PVC without primer in the preparation of primer-free edge-sealing materials. "Primer-free" means that there is no primer between the insert and the edge-sealing material.

[0026] This invention discloses the application of the above-mentioned ASA material for bonding with PVC without primer and PVC in the preparation of primer-free edge-sealing materials; wherein, the ASA material for bonding with PVC without primer is an insert and PVC is an edge-sealing material.

[0027] Currently, most automotive parts use soft PVC for glass edging. Inserts and frames typically use PP+GF or nylon with glass fiber, which have poor compatibility with soft PVC. A primer is needed to increase the adhesion of the soft and hard adhesives. The introduction of the primer (adhesive) increases the product molding process, increases costs, and also increases VOC emissions from automotive parts. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of traditional PVC edging automotive insert materials.

[0029] Figure 2 This is a schematic diagram of the PVC edge-sealing automotive insert material without primer coating according to the present invention.

[0030] Figure 3 The image shows a cavity appearing after a knife test was performed on an existing soft PVC edge-sealing SAN material reinforced with a primer-free coating.

[0031] Figure 4 The image shows that no voids appeared after the modified ASA material of Example 3 of this invention was cut open with a knife during the edge-wrapping injection molding test.

[0032] Figure 5 The image shows another product from Example 3 of this invention, where no voids were found after the modified ASA material was injected and cut with a knife. Detailed Implementation

[0033] Figure 1 This is a schematic diagram of traditional PVC edging automotive insert materials, mainly PA66 / GF30. PA66 / GF30 has no adhesion to the PVC edging material and requires a primer as an "intermediary bridge" to ensure the insert adheres to the surface of the edging material. Figure 2 This is a schematic diagram of the PVC edge-wrapping automotive insert material of the present invention. The primer-free insert material has good self-adhesion to PVC material through material modification, and does not require primer as an "intermediary". During the edge-wrapping injection molding process, the molten PVC material comes into contact with the primer-free insert in the mold, and the primer-free insert and the soft PVC edge-wrapping material are integrated to form a strong bond.

[0034] The applicant previously disclosed a flexible PVC edge-sealing material with a primer-free reinforced SAN material, its preparation method, and its application. This material uses glass fiber reinforced SAN material and incorporates a toughening agent to promote adhesion to flexible PVC, enabling the modified SAN material to function without a primer. While this reinforced SAN material exhibits good compatibility with flexible PVC and its performance meets the requirements of products that conventionally require a primer, further application revealed a defect: the finished edge-sealed parts exhibit voids when cut with a knife. To address this issue, this invention develops a new modified ASA material—a low-cost, primer-free modified ASA material that can bond with PVC. This solves the primer-free bonding problem, significantly reduces costs, and is highly environmentally friendly. Most importantly, the finished edge-sealed parts do not exhibit voids when cut with a knife.

[0035] In this invention, the weight and percentage of SAN resin, ASA adhesive powder, filler, and ACR are 100%, and the weight percentages of each component are as follows: SAN resin 15-40% ASA adhesive powder 30-50% Calcium carbonate 10-20% ACR 15-40% Processing aids 1-3% Pigment 0-2% Preferred, SAN resin 20-30% ASA adhesive powder 30-40% Calcium carbonate 10-20% ACR 20-30% Processing aids 1-3% Pigment 0-2% Further preferred, SAN resin 20-30% ASA adhesive powder 33-37% Calcium carbonate 12-18% ACR 20-25% Processing aids 1-3% Pigment 0-2% Preferably, the weight percentage of ASA adhesive powder is 34%, 35%, 36%, 17%, or any percentage within that range.

[0036] Preferably, the weight percentage of calcium carbonate is 13%, 14%, 15%, 16%, 17%, or any percentage within that range.

[0037] In this invention, SAN resin is a styrene-acrylonitrile copolymer, AN has a mass percentage of 25% to 35%, and a melt index of 25-35 g / 10 min; ASA adhesive powder is a low-particle-size, high-impact adhesive powder; ACR is formed by emulsion polymerization of methacrylates and acrylates, and is generally used as a processing aid in PVC to reduce processing temperature and improve the plasticizing properties of PVC processing.

[0038] The present invention discloses a low-cost, PVC-compatible, primer-free modified ASA material preparation method. This method involves mixing all raw materials and then adding them to a twin-screw extruder for melt extrusion processing to obtain the low-cost, PVC-compatible, primer-free modified ASA material; or adding each raw material separately to a twin-screw extruder for melt extrusion processing to obtain the same low-cost, PVC-compatible, primer-free modified ASA material. In this invention, the diameter of the twin-screw extruder can be 30–75 mm; the melt processing speed can be 300–1200 rpm; and the temperature can be 190–230 °C.

[0039] The edge-wrapping process is as follows: First, the low-cost modified ASA material of the present invention, which can bond with PVC without primer, is injection molded into the required shape according to conventional methods. Then, it is placed in the edge-wrapping mold as an insert. Next, soft PVC (an existing product) is injection molded onto the insert according to conventional methods for secondary edge-wrapping injection molding. After cooling, the final product, a soft PVC edge-wrapped automotive part, is obtained. The entire process does not require a primer.

[0040] Bond strength: The PVC edge of the insert is injection molded and the bond strength is tested using a tensile testing machine at a speed of 50 mm / min. The maximum force is required to be ≥260 N.

[0041] Room temperature bonding: Injection molding of PVC edge wrapping for inserts. Test by hand to see if the insert can be separated from the PVC, and it is required that there are no voids inside after cutting with a knife (knife test).

[0042] High temperature resistance test: In accordance with the requirements of the automotive parts standard QC-T15-1992, the parts are stored at 85℃ for 24 hours without being separated.

[0043] High and low temperature cycling: In accordance with the requirements of the automotive parts QC-T15-1992 standard, temperature cycling at -30℃ and 80℃ is carried out, each cycle is 24 hours, and 10 cycles are carried out without disconnection.

[0044] Water resistance: According to the requirements of the automotive parts QC-T15-1992 standard, it should not separate after being immersed in 40℃ warm water for 240 hours.

[0045] Visually inspect the entire surface for any voids.

[0046] Costs are calculated based on raw material prices.

[0047] The above methods, including specific feeding and extrusion operations, edge-wrapping operations, and performance testing operations, are conventional techniques. The raw materials used in this invention are all existing products that meet the requirements of conventional automotive parts. Different manufacturers' brands can be substituted for each other without affecting the technical effect of this invention. In the following experiments, the two SAN resins are high-flow SAN resin: 2200 and low-flow SAN resin: 3400; the ASA adhesive powder is HY560; the calcium carbonate is 1200-1500 mesh; the ACR is Formosa Plastics P201; the processing aids are 1 part antioxidant 1010 / 168 (1:1 mass ratio compounded) and 1 part EBS lubricant; the pigment is carbon black masterbatch with a carbon black concentration of 50 wt%; Comparative Example 6 uses a compound of acrylate copolymer (ACR) and ethylene methyl acrylate copolymer (EMA) as a toughening agent, with a weight ratio of 100:50.

[0048] All raw materials are conventionally mixed and then fed into a twin-screw extruder for melt processing. The twin-screw extruder has a diameter of 55mm, a speed of 1000rpm, and a temperature of 220℃. The material is extruded, melt-processed, shaped, and granulated to obtain reinforced SAN material.

[0049] The raw materials for the comparative examples are as follows (unit: kg):

[0050] As can be seen from the above comparison, regardless of the type of SAN resin and ASA adhesive powder used in the compounding, when the amount of ACR is low, the edge bonding result of the product is very poor and cannot be used; SAN requires the combination of ACR and SA adhesive powder to avoid voids; the addition of active GMA actually reduces the bonding performance; unexpectedly, the addition of calcium carbonate in this invention significantly reduces the cost, while maintaining or even slightly improving the bonding performance.

[0051] Currently, the mainstream products on the market are still PVC wrapped with PP. As recorded in CN112961444A, the edge wrapping of this product failed without a primer. The CN112961444A product exhibits good performance after edge wrapping injection molding; it did not detach at room temperature, high temperature, high and low temperature, or in hot water. However, when cut with a knife, internal voids appeared. (See...) Figure 3 This does not meet market requirements. To address this issue, this invention develops a new ASA material. After being edged with conventional PVC, it not only does not detach but also shows no voids in a knife test. (See [link to product description]). Figure 4 as well as Figure 5 The soft PVC edge-wrapped automotive parts prepared twice for Example 3 demonstrate that the product of the present invention can achieve the technological advancement of no voids observed in the knife test.

[0052] This invention enables injection molding of PVC materials without a primer; the process is simple, efficient, low-cost, and commercially viable.

Claims

1. An ASA material for bonding with PVC without primer, comprising SAN resin, ASA adhesive powder, filler, ACR, and additives.

2. The ASA material for bonding with PVC without primer as described in claim 1, characterized in that, The weight ratio of SAN resin, ASA adhesive powder, filler, ACR and additives is (15-40): (30-50): (10-20): (15-40): (1-4).

3. The ASA material for bonding with PVC without primer as described in claim 2, characterized in that, The weight ratio of SAN resin, ASA adhesive powder, filler, ACR and additives is (20-30): (30-40): (10-20): (20-30): (1-4).

4. The preparation method of the ASA material for bonding with PVC without primer as described in claim 1 includes the following steps: mixing SAN resin, ASA adhesive powder, filler, ACR and additives to obtain the ASA material for bonding with PVC without primer.

5. An edge-sealing material comprising the ASA material for bonding with PVC without primer as described in claim 1, and PVC.

6. The method for preparing the edge-sealing material according to claim 5 includes the following steps: using ASA material that can be bonded to PVC without primer as an insert and PVC as the edge-sealing material for edge-sealing injection molding to obtain the edge-sealing material.

7. The method for preparing the edging material according to claim 6, characterized in that, No primer is required during edge-sealing injection molding.

8. An automotive material comprising the ASA material for bonding with PVC without primer as described in claim 1 or the edge-wrapping material as described in claim 5.

9. The application of the ASA material for bonding with PVC without primer as described in claim 1 or the edge-sealing material as described in claim 5 in the preparation or as an automotive material.

10. The application of the ASA material for bonding PVC without primer as described in claim 1 in the preparation of edge-sealing materials.

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