Preparation method and application of modified glass fiber reinforced polypropylene composite material

Abstract

The invention discloses a preparation method and application of a modified glass fiber reinforced polypropylene composite material, and belongs to the field of high polymer materials. The modified glass fiber reinforced polypropylene composite material comprises the following raw materials in parts by weight: 33-76 parts of polypropylene resin; 20 to 50 parts of modified glass fiber; 2 to 8 parts of POE resin; 2-5 parts of a styrene thermoplastic elastomer maleic anhydride graft; the preparation method of the modified glass fiber comprises the following steps: dissolving a coupling agent containing double bonds in a solvent, adding glass fiber, taking out and drying to obtain glass fiber with double-bond functional groups on the surface; and adding the glass fiber containing the double-bond functional group on the surface, maleic anhydride, ethoxyamide wax and an initiator into a reaction kettle for grafting reaction, taking out after the reaction is finished, and drying to obtain the surface-coated modified glass fiber.

Description

Technical Field

[0001] This invention relates to the field of polymer materials, specifically to a method for preparing modified glass fiber reinforced polypropylene composite materials and their applications. Background Technology

[0002] Polypropylene (PP) is a polymer formed by the addition polymerization of propylene. Due to its low density, acid and alkali resistance, insulation properties, and high overall cost-effectiveness, it is widely used in automobiles, home appliances, clothing, and other everyday applications. Glass fiber reinforced polypropylene composites utilize glass fibers to reinforce and modify polypropylene, resulting in a modified and reinforced material with excellent comprehensive mechanical properties such as high strength and impact resistance, further expanding its application areas.

[0003] Currently, the main material used for automotive dashboard frames is glass fiber reinforced polypropylene. When assembling the dashboard, the frame needs to be bonded to the PVC slush-molded skin using polyurethane. However, polypropylene is a non-polar material and therefore cannot be directly bonded to polyurethane adhesive. Surface treatment is generally required to activate the material's surface activity and generate polar groups, thus enabling the bonding of the assembly components. Currently, the main industrial method for surface activation treatment of dashboard frames is flame treatment, which uses flame burning to generate polar groups. However, this method has drawbacks such as high equipment and maintenance costs, difficulty in parameter control, reliance on experience, potential flame hazards, and the generation of harmful substances during the flame treatment process. Currently, conventional PP-filled material components requiring improved surface polarity generally use plasma treatment. Plasma treatment offers advantages such as good cleaning effect, precise surface modification, environmental friendliness, high efficiency, strong compatibility, simple operation, no secondary pollution, and long-lasting treatment results. Plasma bombardment breaks the molecular chains on the material surface, generating numerous dangling bonds and polar groups, such as hydroxyl and carboxyl groups, significantly improving surface activity and surface energy, and enhancing the surface's adhesion to solder, coatings, adhesives, and other materials. While plasma treatment is gradually being adopted in the automotive industry, for glass fiber reinforced polypropylene (GFRP) materials, the surface often lacks sufficient active agents due to the influence of glass fiber filler, thus hindering its widespread application. Therefore, inventing a glass fiber reinforced polypropylene composite material suitable for plasma surface treatment is of significant value. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a method for preparing modified glass fiber reinforced polypropylene composite materials and their applications.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A first aspect of the present invention relates to a modified glass fiber reinforced polypropylene composite material, comprising the following raw materials in parts by weight:

[0007] 33-76 parts of polypropylene resin;

[0008] 20-50 parts of modified glass fiber;

[0009] 2-8 parts of POE resin;

[0010] 2-5 parts of maleic anhydride grafted onto styrene-based thermoplastic elastomers;

[0011] The method for preparing the modified glass fiber includes the following steps:

[0012] A coupling agent containing double bonds is dissolved in a solvent and glass fiber is added. The fiber is then removed and dried to obtain glass fiber with double bond functional groups on its surface.

[0013] Glass fibers with double bond functional groups on their surface were grafted with maleic anhydride, ethoxyamide wax and an initiator in a reaction vessel. After the reaction was completed, the fibers were removed and dried to obtain surface-coated modified glass fibers.

[0014] The present invention uses copolymer polypropylene because copolymer polypropylene contains PE elastomer segments, which reduces the regularity of the molecular chain, thereby reducing the crystallinity of the resin system and making it more conducive to activating surface activity during plasma treatment.

[0015] Furthermore, this invention employs the addition of POE resin. On one hand, the addition of POE further reduces the crystallinity of the polypropylene resin; on the other hand, after plasma treatment, the surface energy of POE increases significantly, resulting in a marked improvement in wettability and adhesion, and the treatment effect is maintained for a relatively long time. Due to the high mobility of the POE molecular chain, the polar groups formed after treatment are easily flipped or migrated inward, resulting in a relatively high exposure degree of surface-active groups, thereby increasing the duration of the treatment effect.

[0016] Furthermore, the present invention uses bisphenol A epoxy resin as a surfactant because epoxy resin itself has high polarity, which can improve the surface polarity of the polypropylene system, thereby modifying and enhancing the bonding force between the polypropylene composite material and the polyurethane resin.

[0017] Furthermore, this invention employs styrene-based thermoplastic elastomer maleic anhydride grafts as a resin polarity modifier. By introducing highly polar side groups (maleic anhydride grafts) onto the main chain of the styrene-based thermoplastic elastomer, these grafts can act as a bridge to improve the adhesion and compatibility between polar and non-polar materials in the polypropylene system, and improve the compatibility between glass fiber and polypropylene resin. In addition, the styrene-based thermoplastic elastomer maleic anhydride grafts can better enhance the surface energy of the polypropylene system, thereby improving the adhesive properties of the polypropylene composite material. After maleic anhydride (MAH) is grafted onto the main chain of the styrene-based thermoplastic elastomer, polar carboxyl and ester groups are introduced. These polar groups increase the polarity of the material surface, thereby increasing the surface energy. Polar groups can interact with water molecules or other polar substances in the air, enhancing the wettability and adsorption of material surfaces. During the coating process, the maleic anhydride groups of styrene-based thermoplastic elastomers grafted with maleic anhydride can form hydrogen bonds or chemical bonds with polar groups (such as hydroxyl and amino groups) on the surface of the adherend, enhancing interfacial adhesion. This stronger adhesion also implies an increase in material surface energy, as surface energy is closely related to adhesive force.

[0018] Preferably, the styrene-based thermoplastic elastomer maleic anhydride graft is maleic anhydride-grafted SEBS with a grafting rate of 0.6-1.8%.

[0019] Preferably, the melt flow rate of the polypropylene resin is 10-40 g / 10 min when tested at 230°C and 2.16 kg.

[0020] Preferably, the melt flow rate of the POE resin is 1 to 10 g / 10 min when tested at 190°C and 2.16 kg.

[0021] Preferably, the processing aid includes at least one of antioxidants, lubricants, and colorants.

[0022] Furthermore, the production steps of the surface-modified glass fiber are as follows:

[0023] S1. Dissolve the coupling agent containing double bonds in chloroform at a mass ratio of 1:5 to form solution A. Add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0024] S2. The product obtained in step S1, maleic anhydride, ethoxyamide wax and initiator are added to the reaction vessel in the proportion of (91.5~97.9) / (1~5) / (1~3) / (0.1~0.5). Chloroform solvent is injected and nitrogen gas is introduced for protection. The mixture is stirred in the reaction vessel and a grafting reaction occurs. After the reaction is completed, the product is taken out and dried to obtain surface-coated modified glass fiber.

[0025] Preferably, the coupling agent for the double bond is at least one of vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, and γ-methacryloyloxypropyltrimethoxysilane.

[0026] Preferably, the ethoxyamide wax is a high-carbon-chain ethoxyamide wax with both lipophilic and hydrophilic amphoteric groups, which can effectively improve the surface polarity of the material.

[0027] Preferably, the initiator is dicumyl peroxide (DCP).

[0028] Furthermore, the preparation method of the modified glass fiber reinforced polypropylene composite material is as follows: polypropylene resin, POE resin, compatibilizer, surfactant, and processing aid are mixed and added to the main feed port of an extruder, and modified glass fiber is added from the side feed port to coat the surface. The mixture is then melted, extruded, granulated, and dried to obtain a modified glass fiber reinforced polypropylene composite material.

[0029] Preferably, the extruder temperature is 200-220°C, and the extruder screw speed is 350-450 rpm.

[0030] Furthermore, the obtained modified glass fiber reinforced polypropylene composite material is injection molded into a sample, and after plasma treatment, it can be directly applied to polyurethane adhesives for bonding.

[0031] A second aspect of the present invention relates to a method for preparing a modified glass fiber reinforced polypropylene composite material, comprising the following steps:

[0032] A coupling agent containing double bonds is dissolved in a solvent and glass fiber is added. The fiber is then removed and dried to obtain glass fiber with double bond functional groups on its surface.

[0033] Glass fibers with double bond functional groups on their surface are grafted with maleic anhydride, ethoxyamide wax and initiator in a reaction vessel. After the reaction is completed, the fibers are removed and dried to obtain surface-coated modified glass fibers.

[0034] Take the following raw materials in parts by weight: 33-76 parts of polypropylene resin, 2-8 parts of POE resin and 2-5 parts of styrene-based thermoplastic elastomer maleic anhydride graft, mix them together; then add 20-50 parts by weight of surface-coated modified glass fiber, melt-molde to obtain the modified glass fiber reinforced polypropylene composite material.

[0035] A third aspect of the present invention relates to the application of the above-described modified glass fiber reinforced polypropylene composite material in the preparation of automotive dashboards.

[0036] The beneficial effects of this invention are:

[0037] The modified glass fiber reinforced polypropylene material prepared by the present invention improves the surface polarity of the material on the one hand, and further improves the surface polarity after plasma surface treatment, which greatly improves the bonding force with polyurethane foam or hot melt adhesive, and enriches the application limitations of the material. Detailed Implementation

[0038] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] Polyurethane resin: melt flow rate 30g / 10min, grade K7227H, Wuhan Petrochemical;

[0040] POE resin: melt flow rate 5 g / 10 min, grade 8842, Dow;

[0041] Fiberglass: Grade 248A, Owens Corning;

[0042] Compatibilizer, maleic anhydride grafted SEBS, maleic anhydride grafting rate 1.3%, GMP 5601, Ningbo Nengzhiguang New Material Technology Co., Ltd.

[0043] Surfactant, bisphenol A type epoxy resin, KD-213, Guodu Chemical;

[0044] Vinyltrimethoxysilane, 171, Aikepu New Materials;

[0045] High-carbon chain ethoxyamide wax, KF027, Zhejiang Jiahua;

[0046] In the embodiments of this application, unless otherwise specified, the number of parts of each raw material is by weight or mass.

[0047] Example 1

[0048] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0049] S2. Add the product obtained in step S1, maleic anhydride, high-carbon chain ethoxyamide wax and DCP to a reaction vessel in a ratio of 91.5 / 5 / 3 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reaction vessel to 100°C under reflux, stir and allow the grafting reaction to occur. After the reaction is complete, remove the vessel and dry it to obtain surface-coated modified glass fiber.

[0050] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from the screw zone 1 to the tenth zone is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a modified glass fiber reinforced polypropylene composite material.

[0051] Example 2

[0052] S1, same as embodiment S1;

[0053] S2. Add the product obtained in step S1, maleic anhydride, high carbon chain ethoxyamide wax and DCP to the reaction vessel at a ratio of 94.5 / 3.5 / 1.8 / 0.2, inject chloroform solvent and purge with nitrogen for protection, heat to 100°C and reflux in the reaction vessel, stir and allow the grafting reaction to occur, remove and dry after the reaction is complete to obtain surface-coated modified glass fiber.

[0054] S3. Mix 62 parts of polypropylene resin, 4 parts of POE resin, 3 parts of compatibilizer, 1 part of surfactant, 0.3 parts of antioxidant 1010, 0.2 parts of antioxidant 168, and 0.5 parts of lubricant and add them to the main feed port of the extruder. Add 30 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from zone 1 to zone 10 of the screw is 160℃, 200℃, 200℃, 210℃, 210℃, 220℃, 220℃, 210℃, 210℃, and 200℃, respectively, to obtain a modified glass fiber reinforced polypropylene composite material.

[0055] Example 3

[0056] S1, same as embodiment S1;

[0057] S2. Add the product obtained in step S1, maleic anhydride, high carbon chain ethoxyamide wax and DCP to a reaction vessel at a ratio of 95 / 3 / 1.6 / 0.4, inject chloroform solvent and purge with nitrogen for protection, heat to 100°C under reflux in the reaction vessel, stir and allow the grafting reaction to occur, remove and dry after the reaction is complete to obtain surface-coated modified glass fiber.

[0058] S3. Mix 46 parts of polypropylene resin, 6 parts of POE resin, 4 parts of compatibilizer, 2 parts of surfactant, 0.3 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of lubricant, and 1 part of black masterbatch; add the mixture to the main feed port of the extruder. Add 40 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry the mixture. The extrusion temperatures from screw zone 1 to zone 10 are 160℃, 200℃, 200℃, 210℃, 210℃, 220℃, 220℃, 210℃, 210℃, and 200℃, respectively, to obtain a modified glass fiber reinforced polypropylene composite material.

[0059] Example 4

[0060] S1, same as embodiment S1;

[0061] S2. Add the product obtained in step S1, maleic anhydride, high carbon chain ethoxyamide wax and DCP to a reaction vessel at a ratio of 95 / 3 / 1.6 / 0.4, inject chloroform solvent and purge with nitrogen for protection, heat to 100°C under reflux in the reaction vessel, stir and allow the grafting reaction to occur, remove and dry after the reaction is complete to obtain surface-coated modified glass fiber.

[0062] S3. Mix 33 parts of polypropylene resin, 8 parts of POE resin, 5 parts of compatibilizer, 2 parts of surfactant, 0.3 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of lubricant, and 1 part of black masterbatch; add the mixture to the main feed port of the extruder; add 50 parts of modified glass fiber from the side feed port to coat the surface; melt, extrude, granulate, and dry the mixture. The extrusion temperatures from screw zone 1 to zone 10 are 160℃, 200℃, 200℃, 210℃, 210℃, 220℃, 220℃, 210℃, 210℃, and 200℃, respectively, to obtain a modified glass fiber reinforced polypropylene composite material.

[0063] Comparative Example 1

[0064] 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 were mixed and added to the main feed port of the extruder. 20 parts of glass fiber were added from the side feed port. The mixture was melted, extruded, granulated, and dried. The extrusion temperatures from screw zone 1 to zone 10 were 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0065] Comparative Example 2

[0066] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0067] S2. Add the product obtained in step S1, maleic anhydride, high-carbon chain ethoxyamide wax and DCP to a reaction vessel in a ratio of 91.5 / 5 / 3 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reaction vessel to 100°C under reflux, stir and allow the grafting reaction to occur. After the reaction is complete, remove the vessel and dry it to obtain surface-coated modified glass fiber.

[0068] S3. Mix 78 parts of polypropylene resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from zone 1 to zone 10 of the screw is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0069] Comparative Example 3

[0070] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0071] S2. Add the product obtained in step S1, maleic anhydride, high carbon chain ethoxyamide wax and DCP to the reaction vessel in a ratio of 91.5 / 5 / 3 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reaction vessel to 100°C under reflux, stir and allow the grafting reaction to occur. After the reaction is complete, remove the product and dry it to obtain surface-coated modified glass fiber.

[0072] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168; add the mixture to the main feed port of the extruder; add 20 parts of modified glass fiber from the side feed port to coat the surface; melt, extrude, granulate, and dry the mixture. The extrusion temperatures from screw zone 1 to zone 10 are 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0073] Comparative Example 4

[0074] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0075] S2. Add the product obtained in step S1, maleic anhydride, high-carbon chain ethoxyamide wax and DCP to a reaction vessel in a ratio of 91.5 / 5 / 3 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reaction vessel to 100°C under reflux, stir and allow the grafting reaction to occur. After the reaction is complete, remove the vessel and dry it to obtain surface-coated modified glass fiber.

[0076] S3. Mix 78 parts of polypropylene resin, 2 parts of POE resin, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from the screw zone 1 to the tenth zone is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0077] Comparative Example 5

[0078] S1. Glass fiber, maleic anhydride, high-carbon chain ethoxyamide wax and DCP are added to a reaction vessel in a ratio of 91.5 / 5 / 3 / 0.5. Chloroform solvent is injected and nitrogen gas is introduced for protection. The reaction vessel is heated to reflux at 100°C, stirred and a grafting reaction is carried out. After the reaction is completed, the glass fiber is removed and dried to obtain surface-coated modified glass fiber.

[0079] S2. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from zone 1 to zone 10 of the screw is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0080] Comparative Example 6

[0081] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0082] S2. Add the product obtained in step S1, maleic anhydride, and high-carbon chain ethoxyamide wax to a reaction vessel at a ratio of 91.5 / 5 / 3. Inject chloroform solvent and purge with nitrogen for protection. Heat the reaction vessel to 100°C under reflux, stir, and allow the grafting reaction to occur. After the reaction is complete, remove the vessel and dry it to obtain surface-coated modified glass fiber.

[0083] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from the screw zone 1 to the tenth zone is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0084] Comparative Example 7

[0085] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0086] S2. Add the product obtained in step S1, maleic anhydride, and DCP to the reactor in a ratio of 91.5 / 5 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reactor to 100°C under reflux, stir, and allow the grafting reaction to occur. After the reaction is complete, remove the reactor and dry it to obtain surface-coated modified glass fiber.

[0087] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from the screw zone 1 to the tenth zone is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0088] Comparative Example 8

[0089] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0090] S2. The product obtained in step S1, high carbon chain ethoxyamide wax, and DCP are added to the reaction vessel at a ratio of 91.5 / 3 / 0.5. Chloroform solvent is injected and nitrogen gas is introduced for protection. The mixture is heated to reflux at 100°C in the reaction vessel, stirred, and a grafting reaction occurs. After the reaction is completed, the mixture is removed and dried to obtain surface-coated modified glass fiber.

[0091] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, and 0.2 parts of antioxidant 168 and add them to the main feed port of the extruder. Add 20 parts of modified glass fiber from the side feed port to coat the surface. Melt, extrude, granulate, and dry. The extrusion temperature from the screw zone 1 to the tenth zone is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃, respectively, to obtain a glass fiber reinforced polypropylene composite material.

[0092] Comparative Example 9

[0093] S1. Dissolve vinyltrimethoxysilane in chloroform at a mass ratio of 1:5 to form solution A, and add glass fiber to solution A and stir. The mass ratio of glass fiber to solution A is 1:4. Then filter, remove and dry to obtain glass fiber with double bond functional groups on the surface.

[0094] S2. Add the product obtained in step S1, maleic anhydride, and DCP to the reactor in a ratio of 91.5 / 5 / 0.5. Inject chloroform solvent and purge with nitrogen for protection. Heat the reactor to 100°C under reflux, stir, and allow the grafting reaction to occur. After the reaction is complete, remove the reactor and dry it to obtain surface-coated modified glass fiber.

[0095] S3. Mix 76 parts of polypropylene resin, 2 parts of POE resin, 2 parts of compatibilizer, 0.5 parts of surfactant, 0.3 parts of antioxidant 1010, 0.2 parts of antioxidant 168, and 0.3 parts of high-carbon chain ethoxyamide wax; add to the main feed port of the extruder; add 20 parts of surface-coated modified glass fiber from the side feed port; melt, extrude, granulate, and dry. The extrusion temperature from zone 1 to zone 10 of the screw is 160℃, 190℃, 190℃, 200℃, 200℃, 210℃, 210℃, 210℃, 200℃, and 200℃ respectively to obtain a glass fiber reinforced polypropylene composite material.

[0096] In some existing technologies, the most intuitive and common approach to improving the surface properties of a polymer matrix (such as polypropylene) is to directly add a modifier to the matrix, disperse it throughout the matrix, and then enrich it on the surface through its own migration. However, in some embodiments of this application, a high-carbon chain ethoxyyl group is coated onto glass fibers and then added to the polypropylene composite material along with the glass fibers.

[0097] Specifically, modifying the surface of glass fibers with high-carbon-chain ethoxyamide wax may not only enhance the interfacial bonding between the glass fibers and polypropylene, but also introduce the polar characteristics of the high-carbon-chain ethoxyamide wax into the interfacial region. This could allow the interfacial region to both reinforce and improve surface tension, achieving a multifunctional composite.

[0098] The modified polypropylene composite material of the above-mentioned examples and the glass fiber reinforced polypropylene composite material of the comparative examples were injection molded into planar samples and subjected to plasma treatment. The surface of the planar sample was excited by high frequency using a Weide WD-PLM400 plasma cleaner at a frequency of 40KHz, a treatment power of 2KW, and a time of 30s. Then, the dyne value of the sample surface was tested. A layer of polyurethane hot melt adhesive with a thickness of about 1mm was sprayed on the sample surface, and 3D mesh was laid flat on the sample surface. The sample was treated in a 100℃ oven for 2 minutes, and then removed and left to stand at room temperature for 24 hours. The adhesion strength between the 3D mesh and the sample was tested.

[0099] Table 1 shows the surface dyne values, plasma-treated dyne values, and adhesive strength test results of the composite material samples prepared in Examples 1-4 and Comparative Examples 1-9, as well as the adhesive strength test results of the plasma-treated samples and the 3D mesh adhesive. The dyne values ​​were directly displayed using a dyne pen, and the adhesive strength test was conducted according to the ASTM D1623 test standard.

[0100] Table 1

[0101]

[0102]

[0103] As can be seen from Examples 1 to 4, the modified glass fiber reinforced polypropylene composite material obtained by processing surface-coated glass fiber with specific resin, POE, compatibilizer, and surfactant according to a specific process has a good yenne value. Furthermore, the yenne value increases significantly after plasma treatment, and it exhibits very high adhesive strength with 3D mesh. As can be seen from Examples 1 and Comparative Examples 1 to 8, when the glass fiber surface is not sufficiently modified and no specific substances are added during extrusion, the resulting glass fiber reinforced polypropylene composite material not only has a lower surface yenne value, but also fails to acquire a good yenne value after plasma treatment, thus directly resulting in poor adhesive bonding with 3D mesh. As can be seen from Comparative Example 9, compared to adding high-carbon chain ethoxyamide wax to glass fiber before mixing, the product performance obtained by directly adding high-carbon chain ethoxyamide wax is significantly reduced.

[0104] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0105] The foregoing has shown and described 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. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A modified glass fiber reinforced polypropylene composite material, characterized in that, Including the following parts by weight of raw materials: 33-76 parts of polypropylene resin; 20-50 parts of modified glass fiber; 2-8 parts of POE resin; 2-5 parts of maleic anhydride grafted onto styrene-based thermoplastic elastomers; The method for preparing the modified glass fiber includes the following steps: A coupling agent containing double bonds is dissolved in a solvent and glass fiber is added. The fiber is then removed and dried to obtain glass fiber with double bond functional groups on its surface. Glass fibers with double bond functional groups on their surface were grafted with maleic anhydride, ethoxyamide wax and an initiator in a reaction vessel. After the reaction was completed, the fibers were removed and dried to obtain surface-coated modified glass fibers.

2. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The coupling agent for the double bond is at least one of vinyltrimethoxysilane, vinyltri(2-methoxyethoxy)silane, and γ-methacryloyloxypropyltrimethoxysilane.

3. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The ethoxyamide wax is a high-carbon chain ethoxyamide wax with both lipophilic and hydrophilic amphoteric groups.

4. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The initiator is dicumyl peroxide.

5. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The mass ratio of glass fiber with double bond functional groups on its surface to maleic anhydride, ethoxyamide wax and initiator is (91.5~97.9) / (1~5) / (1~3) / (0.1~0.5).

6. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The polypropylene resin is a copolymer polypropylene resin.

7. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, The styrene-based thermoplastic elastomer maleic anhydride graft is maleic anhydride-grafted SEBS with a grafting rate of 0.6% to 1.8%.

8. The modified glass fiber reinforced polypropylene composite material according to claim 1, characterized in that, It also includes at least one of antioxidants, lubricants, and colorants.

9. A method for preparing a modified glass fiber reinforced polypropylene composite material, comprising the following steps: A coupling agent containing double bonds is dissolved in a solvent and glass fiber is added. The fiber is then removed and dried to obtain glass fiber with double bond functional groups on its surface. Glass fibers with double bond functional groups on their surface are grafted with maleic anhydride, ethoxyamide wax and initiator in a reaction vessel. After the reaction is completed, the fibers are removed and dried to obtain surface-coated modified glass fibers. Take the following raw materials by weight: 33-76 parts of polypropylene resin, 2-8 parts of POE resin and 2-5 parts of styrene-based thermoplastic elastomer maleic anhydride graft, mix them, and add them to the main feed port of the extruder; then add 20-50 parts by weight of surface-coated modified glass fiber from the side feed port of the extruder, melt, extrude, mold, and granulate to obtain the modified glass fiber reinforced polypropylene composite material.

10. The application of the modified glass fiber reinforced polypropylene composite material according to any one of claims 1 to 8 in the preparation of automotive dashboards.

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