Yellowing-resistant reinforced nylon 66 material and preparation method thereof
Technical Field
The invention relates to the field of macromolecules, and particularly relates to a yellowing-resistant reinforced nylon 66 material and a preparation method thereof.
Background
Nylon 66 is used as engineering plastic and widely applied to different industries such as automobiles, electronic appliances, civil products and the like; especially, after the glass fiber is reinforced, the strength and the heat resistance are greatly improved, and the application range of the glass fiber reinforced heat-resistant glass fiber is greatly expanded. However, the amido bond in the molecular structure of the material has strong reducibility, so the material is very easy to be oxidized and yellowed in the drying process and the injection molding processing process, and the application of the material to light-colored products is limited.
At present, two ways are mainly adopted for improving the color change of nylon 66, one way is the process of directly adding an antioxidant to relieve the color change; another way is to make the alloy by adding some of the same kind of materials with low discoloration.
However, for high molecular materials, both of the above two approaches have drawbacks; wherein, the direct addition of the antioxidant has limited effect because of low addition amount and difficult uniform dispersion; while the direct addition of low discoloration materials to make the alloy would compromise the high strength of nylon 66. Therefore, a nylon 66 material with good yellowing resistance on the basis of ensuring the mechanical property of the material is urgently needed to be found.
Disclosure of Invention
The technical problem to be solved is as follows: the invention aims to provide a yellowing-resistant reinforced nylon 66 material, which inhibits the yellowing of reinforced nylon 66, ensures the mechanical property of the material and solves the application problem of reinforced nylon 66 on light-colored products. .
The technical scheme is as follows: the yellowing-resistant reinforced nylon 66 material comprises the following components in percentage by weight:
nylon 66100 parts,
10-50 parts of long carbon chain nylon,
40-80 parts of alkali-free glass fiber,
1-3 parts of functional monomer,
0.5 to 1.5 portions of coupling agent,
0.5 to 1.5 portions of phosphate heat stabilizer,
0.5-1.5 parts of antioxidant;
wherein the functional monomer is a group which chemically reacts with a nylon amido bond.
Further, the long carbon chain nylon is one or more of nylon 610, nylon 612, nylon 1010, nylon 1012 or nylon 1212.
Further, the functional monomer of the yellowing-resistant reinforced nylon 66 material is one or more of maleic anhydride, acrylic acid or methacrylic acid.
Further, the relative viscosity of the nylon 66 is 1.8-4.0.
Further, the anti-yellowing reinforced nylon 66 material is characterized in that the coupling agent is one or more of a silane coupling agent, an aluminate coupling agent or a carbonate coupling agent.
Further, the yellowing-resistant reinforced nylon 66 material is characterized in that the phosphate heat stabilizer is one or more of sodium phosphate, calcium phosphate, iron phosphate, copper phosphate, potassium phosphate or magnesium phosphate.
Further, the anti-yellowing reinforced nylon 66 material is characterized in that the antioxidant is one or more of antioxidant 1010, antioxidant 1076, antioxidant 1098, antioxidant 245 or antioxidant 445.
The preparation method of the yellowing-resistant reinforced nylon 66 material comprises the following steps:
(1) uniformly stirring and mixing the functional monomer, the phosphate heat stabilizer and the coupling agent, adding ethanol for dispersing, diluting and alcoholyzing, and adjusting the pH value of the solution to 3.2-3.8 to obtain special slurry for processing the glass fiber;
(2) infiltrating the glass fiber with special size, and drying to obtain special glass fiber with treated surface;
(3) adding nylon 66, long carbon chain nylon and an antioxidant into a low-speed stirrer, uniformly mixing, adding a small amount of white oil in the mixing process for adhesion, and uniformly mixing to obtain premixed particles;
(4) and (3) adding the premix obtained in the step (3) into a main feeding hopper of a double-screw extruder, and adding the special glass fiber obtained in the step (2) through side feeding, wherein the extrusion temperature is between 240 ℃ and 270 ℃.
Has the advantages that: according to the invention, the phosphate heat stabilizer is dispersed on the surface of the glass fiber innovatively, and the impregnating compound and the reaction type auxiliary agent are simultaneously dispersed on the surface of the glass fiber, so that the resin is ensured to have chemical bond bonding on the interface bonded with the glass fiber, and the heat stabilizer also plays a role sufficiently to inhibit the oxidative discoloration of amido bond. The yellowing-resistant reinforced nylon 66 material disclosed by the invention has the mechanical properties of the material and solves the problem that the light-colored reinforced nylon 66 is easy to yellow.
Detailed Description
Example 1
Stirring and mixing 1.2kg of maleic anhydride, 0.5kg of sodium phosphate and 0.5kg of silane coupling agent KH550 uniformly, adding 10000ml of ethanol for dispersing and alcoholysis, and adjusting the pH value of the solution to 3.2 to obtain special slurry for treating glass fibers; then, soaking 48kg of alkali-free glass fiber by using special slurry, and drying to obtain special glass fiber with the surface treated; adding 100kg of nylon 66, 10kg of nylon 612 and 0.5kg of antioxidant 1098 into a low-speed stirrer, uniformly mixing, and adding a small amount of white oil for adhesion in the mixing process to obtain a premix; finally, adding the premix into a main feeding bin of a double-screw extruder, and adding the treated special glass fiber through side feeding, wherein the extrusion temperature is 240 ℃; and (5) drawing strips, cooling and cutting into granules. The particles were dried in an oven at 80 ℃ for 5 hours and then injection molded with standard ISO bars and standard plaques, and the standard plaques were then baked in an oven at 140 ℃ for 4 hours to test the b-value, each test result is shown in Table 1.
Example 2
1kg of acrylic monomer, 1kg of ferric phosphate and 0.5kg of silane coupling agent KH550 are stirred and mixed uniformly, 10000ml of ethanol is added for dispersion and alcoholysis, and the pH value of the solution is adjusted to 3.8, so that the special slurry for treating the glass fiber is obtained; then, 53kg of glass fiber is soaked by special size and dried to obtain special glass fiber with treated surface; adding 100kg of nylon 66, 20kg of nylon 610, 0.5kg of antioxidant 1098 and 0.5kg of antioxidant 445 into a low-speed stirrer, uniformly mixing, and adding a small amount of white oil for adhesion in the mixing process to obtain a premix; finally, adding the premix into a main feeding bin of a double-screw extruder, and adding the treated special glass fiber through side feeding, wherein the extrusion temperature is 270 ℃; and (5) drawing strips, cooling and cutting into granules. The particles were dried in an oven at 80 ℃ for 5 hours and then injection molded with standard ISO bars and standard plaques, and the standard plaques were then baked in an oven at 140 ℃ for 4 hours to test the b-value, each test result is shown in Table 1.
Example 3
Uniformly stirring and mixing 1.5kg of maleic anhydride, 1.5kg of calcium phosphate and 0.5kg of silane coupling agent KH550, adding 10000ml of ethanol for dispersing and alcoholysis, and adjusting the pH value of the solution to 3.2 to obtain special slurry for treating glass fibers; then soaking 58kg of glass fiber by special size, and drying to obtain special glass fiber with treated surface; adding 100kg of nylon 66, 30kg of nylon 1012 and 0.5kg of antioxidant 1098 into a low-speed stirrer, uniformly mixing, and adding a small amount of white oil for adhesion in the mixing process to obtain a premix; finally, adding the premix into a main feeding bin of a double-screw extruder, and adding the treated special glass fiber through side feeding, wherein the extrusion temperature is 240 ℃; and (5) drawing strips, cooling and cutting into granules. The particles were dried in an oven at 80 ℃ for 5 hours and then injection molded with standard ISO bars and standard plaques, and the standard plaques were then baked in an oven at 140 ℃ for 4 hours to test the b-value, each test result is shown in Table 1.
Example 4
1kg of maleic anhydride, 0.5kg of sodium phosphate and 0.5kg of silane coupling agent KH550 are stirred and mixed uniformly, 10000ml of ethanol is added for dispersion and alcoholysis, and the PH value of the solution is adjusted to 3.8, so that the special size for treating the glass fiber is obtained; then, soaking 40kg of alkali-free glass fiber by special size, and drying to obtain special glass fiber with treated surface; adding 100kg of nylon 66, 10kg of nylon 612 and 0.5kg of antioxidant 1098 into a low-speed stirrer, uniformly mixing, and adding a small amount of white oil for adhesion in the mixing process to obtain a premix; finally, adding the premix into a main feeding bin of a double-screw extruder, and adding the treated special glass fiber through side feeding, wherein the extrusion temperature is 270 ℃; and (5) drawing strips, cooling and cutting into granules. The particles were dried in an oven at 80 ℃ for 5 hours and then injection molded with standard ISO bars and standard plaques, and the standard plaques were then baked in an oven at 140 ℃ for 4 hours to test the b-value, each test result is shown in Table 1.
Example 5
Uniformly stirring and mixing 3kg of acrylic monomer, 1.5kg of ferric phosphate and 1.5kg of silane coupling agent KH550, adding 10000ml of ethanol for dispersing and alcoholysis, and adjusting the pH value of the solution to 3.5 to obtain special slurry for treating glass fibers; then, soaking 80kg of glass fiber by special size, and drying to obtain special glass fiber with treated surface; adding 100kg of nylon 66, 50kg of nylon 610, 0.5kg of antioxidant 1098 and 1kg of antioxidant 445 into a low-speed stirrer, uniformly mixing, and adding a small amount of white oil in the mixing process for adhesion to obtain a premix; finally, adding the premix into a main feeding bin of a double-screw extruder, and adding the treated special glass fiber through side feeding, wherein the extrusion temperature is 270 ℃; and (5) drawing strips, cooling and cutting into granules. The particles were dried in an oven at 80 ℃ for 5 hours and then injection molded with standard ISO bars and standard plaques, and the standard plaques were then baked in an oven at 140 ℃ for 4 hours to test the b-value, each test result is shown in Table 1.
Table 1: comparison of test Performance between examples 1-5 and conventional enhanced PA66
Note: delta b = bAfter baking-bBefore baking
From the test results in table 1, it can be seen that the b value increase of the standard color plate after 4 hours of baking in the oven at 140 ℃ is significantly reduced, the minimum is 1.0, which is far lower than 6 of the common reinforced material, and the strength and toughness of the product are ensured by the strong force between the glass fiber and the value.