Hips composite material as well as preparation method therefor and use thereof

Abstract

Disclosed in the present invention is an HIPS composite material, comprising the following components in parts by weight: 85-90 parts of HIPS, 5.5-9.5 parts of a star-shaped SBS block copolymer and 4-6 parts of mineral oil. By means of adding a specific amount of the star-shaped SBS block copolymer and the specific type of mineral oil to HIPS, the present invention can significantly improve the anti-falling performance of the composite material, and remarkably relieve flow marks generated during injection molding.

Description

A HIPS composite material and its preparation method and application Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a HIPS composite material and a preparation method and application thereof. Background Art

[0002] HIPS material has excellent flowability and resistance to dimensional deformation after injection molding, making it suitable for a wide range of applications. Artillery cases, due to their large overall dimensions and the need to carry and transport ammunition, require excellent material flowability. Furthermore, drop resistance is crucial to ensure the safety of the ammunition. While conventional HIPS materials offer some impact resistance, they struggle to meet these drop resistance requirements.

[0003] Currently, HIPS materials are primarily toughened and modified through SBS block polymer blending. However, to achieve superior toughness, a high content of SBS block copolymer is often added. However, these high-content SBS block copolymers are susceptible to thermal oxidation during the high-temperature blending process, leading to rubber crosslinking. This reduces fluidity, creates surface defects such as crosslinked bumps, and creates tiger-skin-like appearances after injection molding. Furthermore, the material's toughness remains suboptimal. Summary of the Invention

[0004] The object of the present invention is to overcome the above technical defects and provide a HIPS composite material with good drop resistance and no tiger-skin pattern appearance defects after injection molding.

[0005] The present invention is achieved through the following technical solutions:

[0006] A HIPS composite material, comprising the following components in parts by weight:

[0007] HIPS 85-90 copies;

[0008] 5.5-9.5 parts of star-shaped SBS block copolymer;

[0009] 4-6 parts mineral oil;

[0010] Wherein, the kinematic viscosity of the mineral oil is 90-99.9mm 2 / s, open flash point ≥240℃;

[0011] In the star-shaped SBS block copolymer, the weight content of the butadiene segment is in the range of 54-71 wt%;

[0012] The weight content of the rubber phase in the HIPS is in the range of 8-12 wt%.

[0013] The rubber in HIPS refers to the butadiene segments therein, and the rubber content in HIPS can be measured by proton nuclear magnetic spectroscopy. In the technical solution of the present invention, the weight content of the butadiene segments in the star-shaped SBS block copolymer ranges from 55 wt%, 56 wt%, 57 wt%, 58 wt%, 59 wt%, 60 wt%, 61 wt%, 62 wt%, 63 wt%, 64 wt%, 65 wt%, 66 wt%, 67 wt%, 68 wt%, 69 wt%, 70 wt%, and 71 wt%. The weight content of the rubber phase in HIPS ranges from 8.2 wt%, 8.4 wt%, 8.6 wt%, 8.7 wt%, 8.8 wt%, 9.0 wt%, 9.2 wt%, 9.4 wt%, 9.6 wt%, 9.8 wt%, 10. 0 wt%, 10.2 wt%, 10.4 wt%, 10.6 wt%, 10.8 wt%, 11.0 wt%, 11.2 wt%, 11.4 wt%, 11.6 wt%, 11.8 wt%, and 12.0 wt%.

[0014] Among them, the open-cup flash point is determined by the method of reference standard ASTM D92-2012, and the kinematic viscosity is determined by reference to ASTM D445-2015.

[0015] The mineral oil is selected from one or more of paraffin oil and naphthenic oil, preferably naphthenic oil. Compared with paraffin oil, naphthenic oil has better compatibility in the HIPS blend composite material.

[0016] Preferably, the weight content of the rubber phase in the HIPS is in the range of 9-11 wt%.

[0017] Preferably, in the star-shaped SBS block copolymer, the weight content of the butadiene segment is in the range of 58-62 wt%.

[0018] The HIPS has a melt index range of 4-14 g / 10 min, measured according to the method of ASTM D1238-23 under the test conditions of 200° C. and 5 kg.

[0019] The melt index of the star-shaped SBS block copolymer is in the range of 3-10 g / 10 min, and is measured according to the method of ASTM D1238-23 under the test conditions of 190° C. and 5 kg.

[0020] Without impairing the effects of the present invention, the present invention may further include 0-1 parts of antioxidants, 0-1 parts of pigments, and 0-2 parts of antistatic agents, based on weight. The HIPS content in the HIPS composite material of the present invention is not less than 70 wt%.

[0021] The preparation method of the HIPS composite material comprises the following steps: uniformly mixing the components according to the proportion, and extruding and granulating the components through a twin-screw extruder, wherein the screw temperature range is 120-210°C and the speed range is 50-600 rpm.

[0022] The application of HIPS composite materials is used to prepare storage box shells.

[0023] The present invention has the following beneficial effects:

[0024] The present invention significantly improves the drop resistance of the composite material by adding a specific amount of star-shaped SBS block copolymer and a specific type of mineral oil to HIPS, and also significantly improves the tiger stripes produced during injection molding. Specifically, after the star-shaped SBS block copolymer is mixed with a mineral oil of a specific kinematic viscosity, its fluidity is greatly increased, which plays a good dispersing role in the HIPS blending process. The mineral oil with a higher flash point is retained more during the processing process, which plays a good role in rubber dispersion and promoting material flow, thereby improving the tiger stripes; the HIPS rubber content and the star-shaped SBS butadiene segment content are moderate, and the overall strength of the material is good, and the resistance to drop hammer impact is good; if the rubber content in HIPS is too high and / or the star-shaped SBS butadiene segment content is too high, the fluidity of the HIPS blended composite material decreases and tiger stripes are easily formed. If the rubber content is too low and / or the star-shaped SBS butadiene segment content is too low, the matrix is ​​soft and easily deformed and cracked when dropped. Compared with linear structure SBS, star-shaped SBS has a better dispersion effect in HIPS blended composite materials and plays an effective role in drop toughening. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0026] The raw materials used in the present invention come from the following sources:

[0027] HIPS resin was prepared by referring to the method described in the literature (Synthesis, Modification and Characterization of High Impact Polystyrene I. Effect of Agitation Conditions on Impact Properties [J]. Petrochemicals, 2002(09): 725-729). By controlling the amount of polybutadiene chain segments added, HIPS resins with different rubber phase weight contents but similar polymerization degrees were obtained; the following was obtained:

[0028] HIPS-1: The weight content of the rubber phase is 8wt%;

[0029] HIPS-2: The weight content of the rubber phase is 9wt%;

[0030] HIPS-3: The weight content of the rubber phase is 11wt%;

[0031] HIPS-4: The weight content of the rubber phase is 12wt%;

[0032] HIPS-5: The weight content of the rubber phase is 6wt%;

[0033] HIPS-6: The weight content of the rubber phase is 15 wt%.

[0034] Star-shaped SBS block copolymers were prepared by referring to the methods described in the literature (Xu Lingyun, Xie Jingwei, Tang Dexian, et al. Research on SBS Thermoplastic Elastomers - Star-shaped SBS Block Copolymers [J]. Journal of Fudan University (Natural Science Edition), 1981(02): 139-147. and Synthetic Rubber Industry Handbook [M]. Lanzhou Chemical Industry Company; Liu Dahua, Chief Editor. Chemical Industry Press. 1991: 1030-1031.) to obtain star-shaped SBS block copolymers with different butadiene segment weight contents but similar polymerization degrees; the following were prepared:

[0035] Star-shaped SBS block copolymer-1 (hereinafter referred to as star-shaped SBS-1): the weight content of butadiene segments is 55wt%;

[0036] Star-shaped SBS block copolymer-2 (hereinafter referred to as star-shaped SBS-2): the weight content of butadiene segments is 58wt%;

[0037] Star-shaped SBS block copolymer-3 (hereinafter referred to as star-shaped SBS-3): the weight content of butadiene segments is 62wt%;

[0038] Star-shaped SBS block copolymer-4 (hereinafter referred to as star-shaped SBS-4): the weight content of butadiene segments is 70wt%;

[0039] Star-shaped SBS block copolymer-5 (hereinafter referred to as star-shaped SBS-5): the weight content of butadiene segments is 50wt%;

[0040] Star-shaped SBS block copolymer-6 (hereinafter referred to as star-shaped SBS-6): the weight content of butadiene segments is 75wt%;

[0041] Linear SBS block copolymers were prepared by referring to the method described in the literature (Synthetic Rubber Industry Handbook [M]. Lanzhou Chemical Industry Company, edited by Liu Dahua. Chemical Industry Press. 1991: 1030-1031) to obtain linear SBS block copolymers with different butadiene segment weight contents; the following were prepared:

[0042] Linear SBS block copolymer A: the weight content of the butadiene segment is 55 wt%.

[0043] Linear SBS block copolymer B: butadiene segment weight content is 70wt%;

[0044] Paraffin oil-1: 50# paraffin oil, kinematic viscosity 50 mm 2 / s, flash point is 230℃, commercially available.

[0045] Paraffin oil-2: 90# paraffin oil, kinematic viscosity 90 mm 2 / s, flash point is 250℃, commercially available.

[0046] Naphthenic oil-1:10# naphthenic oil, kinematic viscosity is 10 mm 2 / s, flash point is 140℃, commercially available.

[0047] Naphthenic oil-2: 50# naphthenic oil, kinematic viscosity 50 mm 2 / s, flash point is 220℃, commercially available.

[0048] Naphthenic oil-3: 90# naphthenic oil, kinematic viscosity 90 mm 2 / s, flash point is 240℃, commercially available.

[0049] Preparation method of HIPS composite material of embodiment and comparative example: all components are mixed uniformly, and granulated by extrusion through a twin-screw extruder, with the temperature of screw zones 1 to 2 being 120°C-190°C, the temperature of screw zones 3 to 5 being 200°C-210°C, the temperature of screw zones 5 to 10 being 200°C-210°C, and the screw speed being 350 rpm-450 rpm.

[0050] Various test methods:

[0051] (1) Drop resistance evaluation: In order to evaluate the drop resistance of materials for mass production, a 100mm×100mm×2mm square plate is subjected to DuPont impact test. The DuPont impact hammer is 2kg and the impact cone radius is 1 / 8 inch. The drop resistance of the material is evaluated by adjusting the height of the hammer.

[0052] (2) Tiger stripe evaluation: To quantitatively evaluate the tiger stripe pattern of the material, rectangular injection molding was performed on the mold. A group of samples were compared and evaluated each time. The same injection molding machine and injection molding process parameters were used (high injection speed, 90% of the machine's maximum injection speed, was used. Tiger stripe is more likely to appear at high speeds). The mold temperature was fixed at 70°C. After the mold temperature stabilized, the tiger stripe evaluation test was started. The maximum size of the tiger stripe pattern was counted on the surface of the molded rectangular plate.

[0053] Table 1: Content of each component of HIPS composite material (parts by weight) and test results

[0054] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 HIPS-1858890 HIPS-285 HIPS-385 HIPS-485 Star SBS-1999976 Naphthenic oil-3666654 Anti-drop height cm81931001059291 Tiger skin pattern size cm00000.500

[0055] It can be seen from Examples 1-4 that, under the preferred HIPS rubber content, the advantage of no tiger stripes can be achieved, and the drop resistance height can also reach above 90 cm.

[0056] Table 2: Content of each component of HIPS composite material (parts by weight) and test results

[0057] Example 7 Example 8 Example 9 Example 10 HIPS-185858585 Star SBS-19 Star SBS-29 Star SBS-39 Star SBS-49 Naphthenic oil-3666 Paraffin oil-26 Anti-drop height cm859810872 Tiger skin pattern size cm000.30.6

[0058] It can be seen from Examples 1 / 7-9 that the preferred star-shaped SBS butadiene content can achieve the advantage of no tiger stripes and the drop resistance height can reach above 85 cm.

[0059] Table 3: Content of each component of HIPS composite material (parts by weight) and test results

[0060] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 HIPS-18585 HIPS-585 HIPS-685 Star SBS-199 Star SBS-59 Star SBS-69 Naphthenic Oil-36666 Anti-drop height cm5011568118 Tiger skin pattern size cm01.502.3

[0061] Comparative Examples 1-4 show that when the rubber content or the star-shaped SBS butadiene chain content in HIPS is too low, although the processing performance is good, the drop resistance is insufficient. When the rubber content or the star-shaped SBS butadiene chain content in HIPS is too high, the processing performance is poor.

[0062] Table 4: Content of each component of HIPS composite material (parts by weight) and test results

[0063] Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 HIPS-1858585858585 Star-shaped SBS-19999 Linear-shaped SBS-A9 Linear-shaped SBS-B9 Naphthenic oil-366 Naphthenic oil-16 Naphthenic oil-26 Paraffin oil-16 Anti-drop height cm747876432338 Tiger skin pattern size cm2.51.31.47.61.64.1

[0064] It can be seen from Comparative Examples 5-7 that the kinematic viscosity of mineral oil is too low, which not only leads to poor anti-drop performance but also poor processing fluidity.

[0065] It can be seen from Comparative Examples 9-10 that the use of linear SBS not only has poor anti-drop performance but also poor processing fluidity.

Claims

1. A HIPS composite material, characterized in that: By weight, it includes the following components: HIPS 85-90 copies; 5.5-9.5 parts of star-shaped SBS block copolymer; 4-6 parts of mineral oil; Wherein, the kinematic viscosity of the mineral oil is 90-99.9 mm 2 / s, open flash point ≥240℃; The weight content of the rubber phase in the HIPS is in the range of 8-12wt%; In the star-shaped SBS block copolymer, the weight content of the butadiene segment is in the range of 54-71 wt%.

2. The HIPS composite material according to claim 1, characterized in that: The mineral oil is selected from one or more of paraffin oil and naphthenic oil, preferably naphthenic oil.

3. The HIPS composite material according to claim 1, characterized in that: The weight content of the rubber phase in the HIPS is in the range of 9-11 wt %.

4. The HIPS composite material according to claim 1, characterized in that: In the star-shaped SBS block copolymer, the weight content of the butadiene segment is in the range of 58-62wt%.

5. The HIPS composite material according to claim 1, characterized in that: The melting index range of the HIPS is 4-14 g / 10 min, and the test conditions are 200° C. and 5 kg.

6. The HIPS composite material according to claim 1, characterized in that: The melt index range of the star-shaped SBS block copolymer is 3-10 g / 10 min, and the test conditions are 190° C. and 5 kg.

7. The HIPS composite material according to claim 1, characterized in that: By weight, it also includes 0-1 part of antioxidant, 0-1 part of pigment and 0-2 parts of antistatic agent.

8. The method for preparing the HIPS composite material according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: mixing the components uniformly according to the proportion, and extruding and granulating the components through a twin-screw extruder, wherein the screw temperature ranges from 120 to 210° C. and the rotation speed ranges from 50 to 600 rpm.

9. Use of the HIPS composite material according to any one of claims 1 to 7, characterized in that: Used to prepare storage box shells.