Preparation method of low-odor long glass fiber reinforced polypropylene composite material

Abstract

The invention discloses a preparation method of a low-odor long glass fiber reinforced polypropylene composite material, the material structure is a polypropylene wrapped long glass fiber structure, the preparation adopts a melt impregnation mode, the odor control method of the long glass fiber reinforced polypropylene composite material adopts a material baking tank baking mode, the material baking time (min) is t, and the material baking cycle interval time (min) is N-delta, delta is a cycle interval time correction coefficient; the odor grade (grade) of the low-odor long glass fiber reinforced polypropylene composite material is Ds, the ratio of the mass of the long glass fiber to the mass of the composite material is x, the standard cycle interval time (min) is N, and the material drying temperature (DEG C) is T; t, Ds and x meet set conditions; according to the preparation method disclosed by the invention, the low-odor long glass fiber reinforced polypropylene composite material with the required odor grade can be accurately prepared according to a formula, a reference rule is provided for employees in the industry, the process test time is greatly shortened, and the low-odor long glass fiber reinforced polypropylene composite material disclosed by the invention is low in condensation component and acetaldehyde content.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials and relates to a method for preparing a low-odor long glass fiber reinforced polypropylene composite material. Background Art

[0002] Long glass fiber reinforced polypropylene composite materials have the characteristics of high mechanical properties and good dimensional stability, and can be used as a substitute for engineering plastics such as nylon for automotive interior structural parts. However, the finished products of long glass fiber reinforced polypropylene composite materials on the market currently have a poor odor, which directly limits their use as automotive interior parts materials. Low-odor long glass fiber reinforced polypropylene composite materials are a high-quality material developed based on the market to solve the requirement of automotive interior parts for materials with good odor.

[0003] The method for preparing low-odor long glass fiber reinforced polypropylene composite materials in the prior art is a particle baking treatment method. The specific method is to place the prepared long glass fiber reinforced polypropylene material into a baking tank, set the baking temperature, take an appropriate amount of material at regular intervals during the baking period to judge the odor level, and continue the baking process if the odor level does not reach the required level until the odor level of the material reaches the required level, then stop baking and cool down and pack. When this method is used to prepare long glass fiber reinforced polypropylene composite materials, since the sampling and evaluation process takes a long time, the baking cannot be stopped after sampling, and the baking can only be stopped after the odor level is judged to reach the required level. Therefore, it causes unnecessary consumption and waste of energy in the entire production process, resulting in high production costs for enterprises. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the preparation method of low-odor long glass fiber reinforced polypropylene composite material in the prior art cannot accurately determine the drying time according to the material odor level requirements, and a preparation method of low-odor long glass fiber reinforced polypropylene composite material is provided. The present invention can accurately determine the purpose of drying time according to the material odor level requirements by controlling the ratio of the long glass fiber mass to the composite material mass; the prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure, and the preparation adopts the melt impregnation method, the ratio of the long glass fiber mass to the composite material mass is adjustable, and the long glass fiber enters the melt impregnation tank after being untwisted by the external unwinding frame, so the long glass fiber reinforced polypropylene composite material of the present invention has good impregnation effect, less glass fiber agglomeration, lower condensation components, and lower acetaldehyde content.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A preparation method of a low-odor long glass fiber reinforced polypropylene composite material, wherein the material structure is a polypropylene wrapped long glass fiber structure, the preparation adopts a melt impregnation method, the odor control method of the long glass fiber reinforced polypropylene composite material is a baking method in a baking tank, the baking time (min) is t, the baking cycle interval time (min) is N-δ, δ is a cycle interval time correction coefficient,; the odor grade (level) of the low-odor long glass fiber reinforced polypropylene composite material is Ds, the ratio of the long glass fiber mass to the composite material mass is x, the standard cycle interval time (min) is N, and the baking temperature (°C) is T;

[0007] t, Ds, x satisfy: 3.5≤Ds≤3.75, t=-540x+600, 0.1≤x≤0.2; 3.5≤Ds≤3.75, t=-768x+690, 0.2<x≤0.3; 3.5≤Ds≤3.75, t=-852x+720, 0.3 <x≤0.4;3.75<Ds≤4.0,t=-612x+480,0.1≤x≤0.2;3.75<Ds≤4.0,t=-800x+510,0.2<x≤0.3;3.75<Ds≤4.0,t=-996x+570,0.3<x≤0.4;

[0008] δ, t satisfy: 200≤t≤350, 1≤δ≤1.5; 350 <t≤500,1.5<δ≤2.5;500<t≤600,2.5<δ≤3;

[0009] N=10, T is 110.

[0010] The traditional method is to give a certain drying time only through empirical judgment, and then take samples to test the odor level after the set drying time is reached to judge whether to stop drying. There is a certain gap and lag between the actual required drying time, the accuracy is not very sufficient, and it will cause unnecessary waste of energy. The preparation method of the low-odor long glass fiber reinforced polypropylene composite material of the present invention can accurately determine the purpose of the drying time according to the material odor level requirement by controlling the ratio of the long glass fiber mass to the composite material mass, which provides a rule for the technical personnel in this industry to prepare the low-odor long glass fiber reinforced polypropylene composite material, shortens the experimental time, and improves the work efficiency. When long glass fiber reinforced polypropylene composite materials are prepared, the odor level of the composite materials is related to the proportion of polypropylene. Under the same baking conditions, the odor levels of composite materials with different ratios of long glass fiber mass to composite material mass are different. This is because the amount of polypropylene used is different. Therefore, when baking, the long glass fiber reinforced polypropylene composite materials with the required odor level cannot be accurately obtained by only setting the same baking time. The present invention explores and analyzes the ratio of different long glass fiber masses to composite material masses through experimental exploration, and obtains the baking time law for preparing low-odor long glass fiber reinforced polypropylene composite materials. The baking time law of the preparation method of low-odor long glass fiber reinforced polypropylene composite materials of the present invention changes with the change of the long glass fiber mass proportion, and is suitable for the preparation of long glass fiber reinforced polypropylene composite materials with a mass proportion of 10 to 40 commonly used, and gets rid of the uncertainty caused by the need to continuously adjust the baking time as the long glass fiber mass proportion changes when judging by experience.

[0011] As the preferred technical solution:

[0012] As mentioned above, a method for preparing a low-odor long glass fiber reinforced polypropylene composite material has the following specific process: first, the odor grade Ds of the low-odor long glass fiber reinforced polypropylene composite material to be prepared and the ratio x of the long glass fiber mass to the composite material mass (that is, the values ​​of Ds and x are set values) are determined, and the baking time t required to be set for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated according to Ds and x (that is, the relationship between x and t is found according to Ds, and t is calculated after x is substituted into the relationship), and the cycle interval correction coefficient δ is determined according to t (that is, the value range of δ is found according to t, and any value is taken within the value range), and then the linear density of the long glass fiber is selected (that is, it is randomly selected from the long glass fibers with different linear densities available in the market), and then the raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder, and the dried long glass fiber enters the impregnation tank under the action of traction after external yarn withdrawal, and then is subjected to drawing, cooling, pelletizing, and drying treatment to prepare the low-odor long glass fiber reinforced polypropylene composite material.

[0013] As mentioned above, a method for preparing a low-odor long glass fiber reinforced polypropylene composite material has the following specific process: first, the odor grade Ds of the low-odor long glass fiber reinforced polypropylene composite material to be prepared and the ratio x of the long glass fiber mass to the composite material mass (i.e., the values ​​of Ds and x are set values) are determined; the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated according to Ds and x (i.e., the relationship between x and t is found according to Ds, and t is calculated after x is substituted into the relationship); at the same time, the cycle interval correction coefficient δ is determined according to t (i.e., the value range of δ is found according to t, and any value is taken within the value range); then, the linear density of the long glass fiber is selected (i.e., randomly selected from the long glass fibers of different linear densities available on the market); and finally, the low-odor long glass fiber reinforced polypropylene composite material is prepared by a melt impregnation process.

[0014] As mentioned above, in the preparation method of a low-odor long glass fiber reinforced polypropylene composite material, the core layer is an externally withdrawn continuous long glass fiber; the externally withdrawn continuous long glass fiber is used as the core layer because only the externally withdrawn long glass fiber can be untwisted in the form of externally withdrawn yarn, and other forms of long glass fibers cannot be untwisted in the form of externally withdrawn yarn.

[0015] In the above-mentioned method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the polypropylene is a blend of homopolypropylene and copolymer polypropylene, and the mass ratio of the homopolypropylene to the copolymer polypropylene is 2.

[0016] In the above-mentioned method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the compatibilizer is maleic anhydride grafted polypropylene.

[0017] In the above-mentioned method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the mass ratio of the compatibilizer to the mass ratio of the long glass fiber reinforced polypropylene composite material is 0.03.

[0018] In the above-mentioned method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the mass ratio of the antioxidant to the long glass fiber reinforced polypropylene composite material is 0.01.

[0019] As mentioned above, in the preparation method of a low-odor long glass fiber reinforced polypropylene composite material, the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min.

[0020] As described above, in the method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the condensed component of the low-odor long glass fiber reinforced polypropylene composite material is 0.5-1.0 mg, the number of agglomerations above 4 mm is 6-10 / 20 boards, and the acetaldehyde content is 20-25 μg / m3. The long glass fiber reinforced polypropylene composite material prepared by the method for preparing the low-odor long glass fiber reinforced polypropylene composite material of the present invention is a polypropylene wrapped long glass fiber structure, and the preparation adopts a melt impregnation method, the ratio of the long glass fiber mass to the composite material mass is adjustable, and the long glass fiber enters the melt impregnation tank after being untwisted by the outer unwinding frame, so the long glass fiber reinforced polypropylene composite material of the present invention has a good impregnation effect, less glass fiber agglomeration, lower condensed components, and lower acetaldehyde content.

[0021] Beneficial effects:

[0022] (1) The present invention can accurately determine the drying time according to the material odor level requirements by controlling the ratio of the long glass fiber mass to the composite material mass, thereby providing a rule for the technical personnel in the industry to prepare low-odor long glass fiber reinforced polypropylene composite materials, shortening the experimental time and improving work efficiency;

[0023] (2) The method for preparing the low-odor long glass fiber reinforced polypropylene composite material of the present invention comprises the following steps: the prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure, the preparation method is a melt impregnation method, the ratio of the long glass fiber mass to the composite material mass is adjustable, and the long glass fiber is untwisted on an external unwinding frame and then enters a melt impregnation tank. Therefore, the long glass fiber reinforced polypropylene composite material of the present invention has a good impregnation effect, less glass fiber agglomeration, lower condensation components, and lower acetaldehyde content. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0025] Example 1

[0026] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0027] (1) Determining the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.7 and x is 0.3;

[0028] (2) Substituting x into the formula t=-768x+690, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 2.3;

[0029] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0030] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0031] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0032] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.7 mg, the number of agglomerates above 4 mm is 7 / 20 boards, and the acetaldehyde content is 22.3 μg / m 3 .

[0033] Comparative Example 1

[0034] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, wherein the long glass fiber yarn is used as a core layer, and when preparing the low-odor long glass fiber reinforced polypropylene composite material, the drying temperature on the drying tank is set to 110°C, and the drying cycle time is N 1 , t 1 is the baking time, δ 1 is the compensation factor for the drying cycle time, so that the odor level of the low-odor long glass fiber reinforced polypropylene composite material is 3.7.

[0035] Specifically, the core layer of Comparative Example 1 is an outward-retracted continuous long glass fiber with a linear density of 2400tex (same as Example 1), the odor level Ds of the low-odor long glass fiber reinforced polypropylene composite material to be prepared is 3.7 (same as Example 1), the mass proportion of the long glass fiber is 0.3 (same as Example 1), the extruder temperature during preparation is 240°C to 290°C (same as Example 1), the impregnation tank temperature is 280°C to 300°C (same as Example 1), the drawing speed is 30-40m / min (same as Example 1), and the drying cycle interval N 1It is 10min. According to experience, a certain amount of drying cycle time compensation can ensure that the volatile small molecules are fully emitted. The drying cycle time δ 1 It takes many experiments to get the result. If many experiments are not carried out, it will not be possible to ensure that the volatile small molecules are fully released. The baking time t 1 Multiple sampling and evaluation are required to confirm that the odor level meets the requirements. Failure to conduct the evaluation may result in the odor level of the material failing to meet the required level, and the evaluation process will result in energy waste.

[0036] Example 2

[0037] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0038] (1) Determine the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.6 and x is 0.15;

[0039] (2) Substituting x into the formula t=-540x+600, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 2.6;

[0040] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0041] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0042] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0043] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.59 mg, the number of agglomerates above 4 mm is 8 / 20 boards, and the acetaldehyde content is 20.8 μg / m 3 .

[0044] Example 3

[0045] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0046] (1) Determine the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.8 and x is 0.35;

[0047] (2) Substituting x into the formula t=-996x+570, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 1.2;

[0048] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0049] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0050] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0051] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.9 mg, the number of agglomerates above 4 mm is 7 / 20 boards, and the acetaldehyde content is 24.1 μg / m 3 .

[0052] Example 4

[0053] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0054] (1) Determining the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 4.0 and x is 0.2;

[0055] (2) Substituting x into the formula t=-612x+480, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 1.6;

[0056] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0057] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0058] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0059] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.86 mg, the number of agglomerates above 4 mm is 6 / 20 boards, and the acetaldehyde content is 24.7 μg / m 3 .

[0060] Example 5

[0061] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0062] (1) Determining the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.5 and x is 0.35;

[0063] (2) Substituting x into the formula t=-852x+720, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 2.2;

[0064] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0065] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0066] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0067] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.52 mg, the number of agglomerates above 4 mm is 9 / 20 boards, and the acetaldehyde content is 20.7 μg / m 3 .

[0068] Example 6

[0069] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0070] (1) Determining the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.8 and x is 0.3;

[0071] (2) Substituting x into the formula t=-800x+510, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 1.3;

[0072] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0073] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0074] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0075] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber is untwisted on the outer unwinding frame and then enters the melt impregnation tank. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.92 mg, the number of agglomerates above 4 mm is 9 / 20 boards, and the acetaldehyde content is 23.5 μg / m 3 .

[0076] Example 7

[0077] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0078] (1) Determining the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.5 and x is 0.25;

[0079] (2) Substituting x into the formula t=-768x+690, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 2.5;

[0080] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0081] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0082] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0083] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.59 mg, the number of agglomerates above 4 mm is 8 / 20 boards, and the acetaldehyde content is 21.1 μg / m 3 .

[0084] Example 8

[0085] A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, the specific steps are as follows:

[0086] (1) Determining the odor grade Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared; wherein Ds is 3.9 and x is 0.1;

[0087] (2) Substituting x into the formula t=-612x+480, the baking time t required for the low-odor long glass fiber reinforced polypropylene composite material to be prepared is calculated, and the cycle interval correction coefficient δ is determined according to t, and δ is 2.1;

[0088] (3) Selecting an externally-retracted continuous long glass fiber with a linear density of 2400tex;

[0089] (4) A low-odor long glass fiber reinforced polypropylene composite material is prepared by melt impregnation; wherein the process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min;

[0090] (5) The raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly, and then enter the impregnation tank through a twin-screw extruder. The dried long glass fiber is withdrawn externally and enters the impregnation tank under the action of traction to be drawn, cooled, pelletized and dried.

[0091] The prepared long glass fiber reinforced polypropylene composite material is a polypropylene wrapped long glass fiber structure. The ratio of the long glass fiber mass to the composite material mass is adjustable. The long glass fiber enters the melt impregnation tank after being untwisted on the outer unwinding frame. The condensed component of the long glass fiber reinforced polypropylene composite material is 0.88 mg, the number of agglomerates above 4 mm is 6 / 20 boards, and the acetaldehyde content is 23.7 μg / m 3 .

Claims

1. A method for preparing a low-odor long glass fiber reinforced polypropylene composite material, characterized in that: The material structure is a polypropylene wrapped long glass fiber structure, and the preparation adopts a melt impregnation method. The odor control method of the long glass fiber reinforced polypropylene composite material is a baking tank baking method. The baking time (min) is t, the baking cycle interval time (min) is N-δ, and δ is the cycle interval time correction coefficient; the odor grade (level) of the low-odor long glass fiber reinforced polypropylene composite material is Ds, the ratio of the long glass fiber mass to the composite material mass is x, the standard cycle interval time (min) is N, and the baking temperature (℃) is T; t, Ds, x satisfy: 3.5≤Ds≤3.75, t=-540x+600, 0.1≤x≤0.2; 3.5≤Ds≤3.75, t=-768x+690, 0.2<x≤0.3; 3.5≤Ds≤3.75, t=-852x+720, 0.3<x≤0.4; 3.75<Ds≤4.0, t=-612x+480, 0.1≤x≤0.2; 3.75<Ds≤4.0, t=-800x+510, 0.2<x≤0.3; 3.75<Ds≤4.0, t=-996x+570, 0.3<x≤0.4; δ and t satisfy: 200≤t≤350, 1≤δ≤1.5; 350<t≤500, 1.5<δ≤2.5; 500<t≤600, 2.5<δ≤3; N=10, T is 110.

2. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 1, characterized in that: The specific process is as follows: first, the odor level Ds and the ratio x of the long glass fiber mass to the composite material mass of the low-odor long glass fiber reinforced polypropylene composite material to be prepared are determined; the required baking time t is calculated according to Ds and x; and the cycle interval correction coefficient δ is determined according to t; then, the raw material polypropylene resin, compatibilizer and antioxidant are put into a high-speed mixer and mixed evenly; then, the raw material polypropylene resin, compatibilizer and antioxidant are put into an impregnation tank through a twin-screw extruder; after the dried long glass fiber is withdrawn externally, it enters the impregnation tank under the action of traction force, and then is subjected to strip drawing, cooling, pelletizing and drying treatment to prepare a low-odor long glass fiber reinforced polypropylene composite material.

3. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: The long glass fiber is a continuous long glass fiber with a linear density of 1200tex, 2400tex or 3600tex.

4. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: Long glass fiber is a continuous long glass fiber with an outward retreating shape.

5. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: Polypropylene is a blend of homopolypropylene and copolymer polypropylene.

6. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 4, characterized in that: The mass ratio of homopolymer polypropylene to copolymer polypropylene is 2.

7. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: The compatibilizer is maleic anhydride grafted polypropylene.

8. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 7, characterized in that: The mass ratio of the compatibilizer to the long glass fiber reinforced polypropylene composite material is 0.

03.

9. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: The mass ratio of antioxidant to long glass fiber reinforced polypropylene composite material is 0.

01.

10. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 2, characterized in that: The process parameters of the long glass fiber reinforced polypropylene composite material are: the extruder temperature is set at 240°C to 290°C, the impregnation tank temperature is set at 280°C to 300°C, and the drawing speed is 30-40m / min.

11. The method for preparing a low-odor long glass fiber reinforced polypropylene composite material according to claim 1, characterized in that: The condensation component of low-odor long glass fiber reinforced polypropylene composite material is 0.5-1.0 mg, the number of agglomerates above 4 mm is 6-10 / 20 boards, and the acetaldehyde content is 20-25 μg / m 3 .