CN1511872A - A kind of nylon particle toughened polypropylene composite material and preparation method thereof - Google Patents

Abstract

A nylon particle toughened polypropylene composite material, the components and content of which are: in parts by weight: polypropylene 40-90, nylon 5-30, interface compatibilizer 5-30, crosslinking agent 0.1-1.0, anti- Oxygen 0.1-0.5, lubricant 0.1-0.5. The preparation steps are as follows: a) pre-mixing ethylene-alpha olefin copolymer and polyolefin at a ratio of 1:1.5-1.5:1, then mixing evenly with grafting monomers, grafting on a twin-screw extruder at 160-220°C branching and granulation to obtain an interfacial compatibilizer; b) premixing in a mixer according to the proportion, extruding and granulating on a twin-screw extruder at 190-240° C. to obtain a nylon particle toughened polypropylene composite material. The polypropylene composite material provided by the invention has the characteristics of high toughness and good comprehensive performance under the synergistic effect of the nylon particles and the deformable and well-bonded interfacial compatibilizer shell on the surface.

Description

A kind of nylon particle toughened polypropylene composite material and preparation method thereof

technical field

The invention relates to a nylon/polypropylene blend material, in particular to a nylon particle toughened polypropylene composite material.

The invention also relates to a method for the preparation of the aforementioned materials.

Background technique

Polypropylene material is widely used in many industries such as home appliances, automobiles, building materials, and agriculture because of its large annual output, low price, good comprehensive performance, low density, and easy molding. However, due to the two main shortcomings of polypropylene materials, poor toughness and low modulus, the application of polypropylene materials as structural materials is limited.

The blending method of adding other polymers to polypropylene is one of the main methods to improve the toughness of polypropylene materials. Adding rubber-like elastomers and blending with polypropylene can effectively improve the toughness of polypropylene materials, but it will cause the modulus of polypropylene materials to drop even lower; adding high-performance polymers such as nylon and blending them can effectively maintain or improve the toughness of polypropylene materials. The modulus of the polypropylene material, but whether the toughness of the polypropylene material can be improved depends on the compatibility of the two and the morphology of the high-performance polymer in the polypropylene matrix.

Gonzalez-Montiel, A. et al reported the addition of maleated ethylene-propylene rubber (EPR) and maleated styrene-butadiene rubber (SBR) in "Polymer Material Science and Engineering" 1993, Volume 70, pages 194-195 A method for improving the toughness of nylon 6/polypropylene blends.

Kim, G.M. and Michler, G.H. et al. in "Polymer Advance Technology", Vol. 9, No. 10-11, 1998, pp. 709-715 and "Acta Polymer", Vol. 49, No. 2-3, pp. 88-95, 1998 reported in polypropylene/nylon (70/30vol.%) by adding maleic anhydride grafted styrene-ethylene-1-butene block copolymer (SEBS-g-MA) to form SEBS-g- MA rubber is the shell, and nylon is the core, that is, the core-shell particles to toughen the polypropylene material.

In the prior art, grafted rubber is used. On the one hand, it acts as an interfacial compatibilizer to improve the compatibility between nylon and polypropylene matrix. On the other hand, it exists as a dispersed phase in the polypropylene matrix or covers the surface of the nylon dispersed phase. Forms nylon-rubber "core-shell" particles, toughens polypropylene material. Since the rubber will be cross-linked due to the action of initiator, heat or shear force during the grafting process, when the partially cross-linked grafted rubber is blended with polypropylene and nylon, it is difficult to regenerate in the polypropylene matrix. The dispersion is uniform, and a thin and uniform shell cannot be formed on the surface of the nylon dispersed phase, so the toughening effect on polypropylene materials is poor.

Contents of the invention

The object of the present invention is to provide a nylon particle toughened polypropylene composite material.

Another object of the present invention is to provide a preparation method of the above materials.

To achieve the above object, the present invention provides a kind of interfacial compatibilizer with good compatibility with polypropylene and nylon. When blended with polypropylene matrix, the interfacial compatibilizer can form a thin film on the surface of nylon dispersed phase. and a uniform shell; at the same time, a cross-linking agent is provided to partially cross-link the shell of the interfacial compatibilizer in place.

The nylon particle toughened polypropylene composite material provided by the invention is made up of the following components and their contents, and the contents are in parts by weight:

Polypropylene 40-90

Nylon 5-30

Interface compatibilizer 5-30

Cross-linking agent 0.1-1.0

Antioxidant 0.1-0.5

Lubricant 0.1-0.5

The polypropylene is homopolypropylene or copolymerized polypropylene, its melt flow rate is 0.1-30.0 g/10 minutes, and the optimum content is 50-70 parts by weight.

The nylon is nylon 6, nylon 66, nylon 1010, its melt flow rate is 0.1-10.0 g/10 minutes, and the optimum content is 15-30 parts by weight.

The interfacial compatibilizer is a graft of ethylene-α-olefin copolymer with 4-10 carbon atoms and a polyolefin blend, its melt flow rate is 0.5-15 g/10 minutes, and the blending ratio is 1: 1.5-1.5:1, the grafting group is a functional group that can react chemically with nylon, specifically maleic anhydride, acrylic acid, methacrylic acid or itaconic acid, etc. The optimum content of the interface compatibilizer is 5- 20 parts by weight.

The crosslinking agent is a bifunctional epoxy resin or a multifunctional epoxy resin.

The antioxidant is tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, 1,1,3-tris(2-methyl-4-hydroxyl-5 - tert-butylphenyl) butane, 4,4-thiobis(6-tert-butyl-3-methylphenol), pentaerythritol bisphosphite bis(2,4-di-tert-butylphenyl)ester, A compound of one or more of tris(2,4-di-tert-butylphenyl) phosphite, etc.

Described lubricant is petroleum resin, polypropylene wax, polyethylene wax, solid paraffin, liquid paraffin, naphthenic oil, lauric acid ester, oleic acid ester, oleic acid, stearic acid ester, stearic acid and its salt such as hard One or more of calcium fatty acid etc.

The preparation method of nylon particle toughened polypropylene composite material of the present invention, comprises the following steps successively:

(1) Pre-mix the ethylene-alpha olefin copolymer and polyolefin at a ratio of 1:1.5-1.5:1, and then mix it evenly with the grafting monomer, and process it on a twin-screw extruder at a processing temperature of 160-220°C Grafting and granulation to obtain the interface compatibilizer.

(2) 40-90 parts of polypropylene, 5-30 parts of nylon, 5-30 parts of interfacial compatibilizer, 0.1-1.0 parts of crosslinking agent, 0.1-0.5 parts of antioxidant, 0.1-0.5 parts of Parts of lubricant are pre-mixed in a high-speed mixer, then extruded and granulated on a twin-screw extruder at 190-240°C to obtain a nylon particle toughened polypropylene composite material.

Although not intended to be limited to theoretical explanations, the possible mechanisms of the present invention are as follows:

Since the interfacial compatibilizer is a graft of ethylene-alpha olefin copolymer and polyolefin blend, which is very similar to the molecular chain structure of the polypropylene matrix, the interfacial compatibilizer has good compatibility with the polypropylene matrix; the graft polarity After the group reacts chemically with the amino group in the nylon molecular chain, the compatibility with the nylon interface increases; the improvement of the compatibility promotes the dispersion of nylon particles in the polypropylene matrix to become smaller and evenly dispersed. Since the molecular chains of the two components contained in the interface compatibilizer do not contain unsaturated bonds, it is not easy to produce crosslinking reactions during the grafting process, so it is easy to disperse when blended with polypropylene and nylon A thin and uniform covering layer is formed on the surface, that is, the shell layer, which enables the nylon particles to deform when the material is impacted. When the cross-linking agent is blended, the formed shell is cross-linked in situ to increase the deformation ability and tear strength of the shell on the surface of the nylon particles. Under the synergy of the deformable and well-bonded interfacial compatibilizer shell on the nylon particle and its surface, the polypropylene matrix is induced to generate shear bands, thereby greatly improving the toughness of the polypropylene material.

The nylon particle toughened polypropylene composite material of the invention has high toughness and good comprehensive performance.

The present invention will be further described below in conjunction with embodiment, wherein embodiment 1-3 is the embodiment that carries out according to the present invention, embodiment 4-6 is the interfacial compatibilizer that does not add grafting group, embodiment 7-8 is No interfacial compatibilizer was added for comparison.

Example 1

Pre-mix ethylene-alpha olefin copolymer and low-density polyethylene at a ratio of 1:1.5, and then mix it with maleic anhydride evenly, and graft it on a twin-screw extruder at a processing temperature of 200-220°C to make Granules were obtained with maleic anhydride grafted polymer as interfacial compatibilizer.

64 parts of homopolypropylene, 30 parts of nylon 6, 6 parts of interfacial compatibilizer, 0.3 part of multifunctional epoxy resin, 0.1 part of pentaerythritol diphosphite bis (2,4-di-tert-butylbenzene Base) ester, 0.2 parts of calcium stearate, after pre-mixing in a high-speed mixer, extrude, water-cool, and granulate on a twin-screw extruder at 230-240 ° C to obtain nylon particle toughened polypropylene composite material. The mechanical properties of the obtained materials are listed in Table 1.

Example 2

Interface compatibilizer is identical with embodiment 1.

52 parts of homopolypropylene, 30 parts of nylon 6, 18 parts of interfacial compatibilizer, 0.3 parts of multifunctional epoxy resin, 0.1 part of pentaerythritol diphosphite bis(2,4-di-tert-butylbenzene Base) ester, 0.2 parts of calcium stearate, pre-mixed in a high-speed mixer, extruded, water-cooled, and granulated on a twin-screw extruder at a processing temperature of 230-240 ° C to obtain nylon particles toughened polypropylene composite material. The mechanical properties of the obtained materials are listed in Table 1.

Example 3

Interface compatibilizer is identical with embodiment 1.

40 parts of homopolypropylene, 30 parts of nylon 6, 30 parts of interfacial compatibilizer, 0.3 parts of multifunctional epoxy resin, 0.1 part of pentaerythritol diphosphite bis (2,4-di-tert-butylbenzene Base) ester, 0.2 parts of calcium stearate, pre-mixed in a high-speed mixer, extruded, water-cooled, and granulated on a twin-screw extruder at a processing temperature of 230-240 ° C to obtain nylon particles toughened polypropylene composite material. The mechanical properties of the obtained materials are listed in Table 1.

Example 4

Pre-mix ethylene-alpha olefin copolymer and low-density polyethylene at a ratio of 1:1.5, extrude and granulate the blend on a twin-screw extruder at a processing temperature of 200-220°C to obtain a blend as an interfacial compatibilizer .

64 parts of homopolypropylene, 30 parts of nylon 6, 6 parts of interfacial compatibilizer, 0.1 part of pentaerythritol bisphosphite bis (2,4-di-t-butylphenyl) ester, 0.2 part of stearin After pre-mixing in a high-speed mixer, extrude, water-cool, and granulate on a twin-screw extruder at 230-240°C to obtain a polypropylene/nylon blend material. The mechanical properties of the obtained materials are listed in Table 1.

Example 5

The interface modifier is the same as in Example 4.

52 parts of homopolypropylene, 30 parts of nylon 6, 18 parts of interfacial compatibilizer, 0.1 part of pentaerythritol bisphosphite bis (2,4-di-t-butylphenyl) ester, 0.2 part of stearin After pre-mixing in a high-speed mixer, extrude, water-cool, and granulate on a twin-screw extruder at 230-240°C to obtain a polypropylene/nylon blend material. The mechanical properties of the obtained materials are listed in Table 1.

Example 6

The interface modifier is the same as in Example 4.

40 parts of homopolypropylene, 30 parts of nylon 6, 30 parts of interfacial compatibilizer, 0.1 part of pentaerythritol bisphosphite bis (2,4-di-t-butylphenyl) ester, 0.2 part of stearin After pre-mixing in a high-speed mixer, extrude, water-cool, and granulate on a twin-screw extruder at 230-240°C to obtain a polypropylene/nylon blend material. The mechanical properties of the obtained materials are listed in Table 1.

Example 7

With 70 parts of homopolypropylene, 30 parts of nylon 6, 0.1 part of pentaerythritol bisphosphite bis (2,4-di-t-butylphenyl) ester, 0.2 part of calcium stearate, pre-prepared in a high-speed mixer After mixing, extrusion, water cooling and granulation are performed on a twin-screw extruder at 230-240° C. to obtain a polypropylene/nylon blend material. The mechanical properties of the obtained materials are listed in Table 1.

Example 8

With 100 parts of homopolypropylene, 0.1 part of pentaerythritol bisphosphite bis (2,4-di-tert-butylphenyl) ester, 0.2 part of calcium stearate, after pre-mixing in high-speed mixer, in twin-screw Extrude at 230-240°C on an extruder, water-cool and granulate to obtain polypropylene material. The mechanical properties of the obtained materials are listed in Table 1.

Table 1. Mechanical properties of polypropylene/nylon composites Notched impact strength (J/m) Flexural modulus (GPa) Bending strength (MPa) Tensile strength (MPa) Elongation at break (%) Example 1 23.8 1.2 50.8 39.7 32.2 Example 2 109.0 0.8 33.3 30.2 182.2 Example 3 182.5 0.5 22.2 24.1 435.6 Example 4 36.0 1.2 41.7 34.1 18.6 Example 5 48.0 1.0 37.1 28.9 19.2 Example 6 70.5 0.7 32.9 26.6 78.5 Example 7 32.5 1.4 48.0 36.9 16.9 Example 8 12.3 1.1 45.2 36.1 655.0

Claims (12)

1. A nylon particle toughened polypropylene composite material, its components and content are as follows, wherein the content is in parts by weight: Polypropylene 40-90; Nylon 5-30; Interfacial compatibilizer 5-30; Crosslinking agent 0.1-1.0; Antioxidant 0.1-0.5; Lubricant 0.1-0.5. 2. The composite material according to claim 1, characterized in that said polypropylene is homopolypropylene or copolymerized polypropylene, and its melt flow rate is 0.1-30.0 g/10 minutes. 3. The composite material according to claim 1 or 2, characterized in that the content of the polypropylene is 50-70 parts by weight. 4. The composite material according to claim 1, characterized in that said nylon is nylon 6, nylon 66 or nylon 1010, and its melt flow rate is 0.1-10.0 g/10 minutes. 5. The composite material according to claim 1 or 4, characterized in that the content of said nylon is 15-30 parts by weight. 6. The composite material according to claim 1, characterized in that: the interfacial compatibilizer is a graft of ethylene-α-olefin copolymer with 4-10 carbon atoms and a polyolefin blend, and its melt flow rate is 0.5-15 g/10 minutes, the blending ratio is 1:1.5-1.5:1. 7. The composite material according to claim 6, wherein the grafting group is maleic anhydride, acrylic acid, methacrylic acid or itaconic acid. 8. The composite material according to claim 1, characterized in that the content of the interface compatibilizer is 5-20 parts by weight. 9. The composite material according to claim 1, characterized in that the crosslinking agent is a bifunctional epoxy resin or a multifunctional epoxy resin. 10. The composite material according to claim 1, characterized in that: said antioxidant is tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, 1,1, 3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 4,4-thiobis(6-tert-butyl-3-methylphenol), pentaerythritol diphosphite A compound of one or more of (2,4-di-tert-butylphenyl) ester and tris(2,4-di-tert-butylphenyl) phosphite. 11. The composite material according to claim 1, characterized in that: the lubricant is petroleum resin, polypropylene wax, polyethylene wax, solid paraffin, liquid paraffin, naphthenic oil, laurate, oleate, oleic acid , one or more of stearic acid esters, stearic acid and salts thereof. 12. A preparation of the composite material as claimed in claim 1, the main steps of which are as follows: a) Pre-mix the ethylene-alpha olefin copolymer and polyolefin at a ratio of 1:1.5-1.5:1, and then mix it evenly with the grafting monomer, graft and granulate at 160-220°C on a twin-screw extruder Obtain interface compatibilizer; b) After pre-mixing in a mixer according to the proportion, extruding and granulating on a twin-screw extruder at 190-240° C. to obtain a nylon particle toughened polypropylene composite material.