CN115558234A - Runner master batch suitable for injection molding of medium-temperature ebonite plastic and preparation method thereof - Google Patents

Abstract

The invention discloses a flow pattern master batch suitable for injection molding of medium-temperature ebonite plastic and a preparation method thereof; the medium-temperature hard glue plastic refers to ABS, HIPS, AS, PA6 and alloy thereof; the master batch comprises: 10 to 50 parts of PET, 10 to 40 parts of PBT, 10 to 80 parts of SEBS or SBS, 5 to 160 parts of plasticizer, 1 to 5 parts of compatibilizer, 0.1 to 1.5 parts of antioxidant, 0.1 to 1.5 parts of lubricant and 1 to 10 parts of pigment; the viscosity of PET and PBT resin is more than 0.8dl/g, and the mass ratio is 3; SEBS or SBS resin with medium or high molecular weight; the flash point of the plasticizer is more than 180 ℃, and the addition amount of the plasticizer is at most twice of the total amount of SEBS or SBS; the compatibilizer is SEBS or SBS grafted maleic anhydride or glycidyl methacrylate. The master batch is suitable for injection molding of medium-temperature ebonite plastics, and can obtain plastic products with good flow pattern appearance effect.

Description

Applicable to medium-temperature hard rubber plastic injection molding rhyolite masterbatch and preparation method thereof

technical field

The invention belongs to the technical field of color masterbatch, and relates to a flow pattern masterbatch suitable for injection molding of medium-temperature hard rubber plastics and a preparation method thereof.

Background technique

Plastic products are widely used in daily necessities, electrical equipment, handicrafts, auto parts and packaging products. As an alternative to painting, spray-free coating has the advantages of environmental protection, one-time molding, cost reduction and shortened production cycle. It can also Give the surface of the product an aesthetic texture imitating natural ecology, such as metal, twinkling starry sky, marble, fluff, fabric and other effects, to enrich consumers' visual experience. With the development of spray-free materials, various differentiated appearance effects are constantly being developed to meet different individual requirements.

To realize the effect of flow pattern on the appearance of plastic products, it is often used to add flow pattern masterbatch to the base material, and use the temperature difference between the plasticization of the base material and the flow pattern color masterbatch to make the flow pattern effect masterbatch in the injection molding process Natural flow is distributed on the surface of the product, resulting in a flow effect. This method can be produced in the existing ordinary injection molding machine, but the disadvantage is that different raw materials will have different molding temperatures. Higher temperature masterbatch with flow effect It melts with the base material at the same time, and the two materials are mixed together to produce the flow pattern effect. If the temperature is low, the flow pattern effect of the color masterbatch is not well plasticized, making the flow pattern uneven, so increasing the injection molding temperature width is the best way to prepare the flow pattern The key to the effect, Chinese patent CN12745665A discloses a polypropylene material injection molding flow pattern effect masterbatch and its preparation method, this method is only suitable for polyolefin materials with lower injection molding temperature, for ABS, HIPS, The color masterbatch of AS, PA6 and other materials will be completely melted and immersed into the substrate, and the flow effect cannot be achieved. At the same time, in order to increase the compatibility between PA and PP, polyolefin materials lower than and close to the processing temperature of PP are added, which will cause the processing injection molding temperature to increase. The range is narrow and it is difficult to control the processing technology. Chinese patent CN108976693A discloses a marble-like masterbatch suitable for ABS and its application method. Two kinds of masterbatches are used to realize the effect of marble and wood grain on plastic profiles. The first masterbatch is mainly PET; the second The masterbatch is made of PBT, and PET, PBT and ABS are used to form marble and wood grain effects. This method uses PET and PBT to make masterbatches respectively, but due to the large difference in processing temperature between PET and PBT, PBT color masterbatches are close to each other during injection molding. The processing temperature of ABS is completely melted, and the color masterbatch has completely entered the base color of the substrate, while the PET color masterbatch is still not melted, causing PET to not disperse, resulting in unnatural flow patterns.

The invention provides a masterbatch of medium-temperature hard rubber plastic injection molding flow pattern, which is prepared by blending PET, PBT, plasticized SEBS/SBS, and compatibilizer as base materials, antioxidants, lubricants, and pigments. Rhythmic masterbatch, since PET and PBT are polyester polymers, they have good compatibility, and the melting point of the blended PBT/PET alloy will approach the middle of the melting point of PBT and PET, reducing the difference between the melting points of the two. The disadvantages are that the fluidity of plasticized SEBS is less affected by temperature, and the compatibilizer improves the compatibility of SEBS and PBT/PET alloy. The processing temperature of the prepared flowline masterbatch is suitable for 235-265°C, which solves the problem that PET is not completely melted when the temperature is slightly low, the flowline is unnatural, and when the processing temperature is slightly high, it is completely melted and immersed in medium-temperature hard rubber plastic products. The background color cannot form the flow pattern effect, and the invention improves the flow pattern processing temperature width, which is beneficial to form a natural flow pattern effect during the processing.

Contents of the invention

In view of the above-mentioned technical problems, the present invention provides a rhyolite masterbatch suitable for injection molding of medium-temperature hard rubber plastics and a preparation method thereof.

The invention relates to a masterbatch suitable for injection molding of medium-temperature hard rubber plastics. The masterbatch includes the following raw materials in parts by weight:

As an embodiment, the medium-temperature hard rubber plastic refers to ABS, HIPS, AS, PA6, etc. and alloys thereof.

As an embodiment, the viscosity of the PET and PBT resins is preferably greater than 0.8dl/g. High viscosity is good for blending PBT/PET alloy, and it is good for flow pattern masterbatch not to be fully immersed in medium temperature hard rubber plastic base material during injection molding process.

As an embodiment, preferably m(PET):m(PBT)=3:7～7:3. It is beneficial for the melting points of the two PET/PBT alloys to move to the middle of the melting points of PBT and PET, and at the same time, the PBT/PET alloy is in a semi-molten state within the processing temperature range.

As an embodiment, the SEBS or SBS resin is one or two of medium and high molecular weight, its styrene content is 28-32%, and the viscosity measured in 10wt% toluene solution at 25°C is 1300-5000cps . Medium and high molecular weight SEBS and SBE are preferred, and the fluidity is less affected by temperature.

As an embodiment, the plasticizer is one of saturated linear naphthenic white oil, aromatic white oil and paraffinic white oil.

As an embodiment, the compatibilizer is SEBS or SBS grafted maleic anhydride (SEBS-g-MAH or SBS-g-MAH) or glycidyl methacrylate (SEBS-g-GMA or SBS-g -GMA) one or both.

As an embodiment, the antioxidant is one or more of antioxidant 1010, antioxidant 1076, and antioxidant 168.

As an embodiment, the lubricant is one or more of stearate, EBS and silicone.

The present invention also relates to a preparation method suitable for injection molding of medium-temperature hard rubber plastics, said method comprising the following steps:

S1. Under the condition of stirring, pour the plasticizer into SEBS or SBS resin; stir for 10-20 minutes, stir well and place it for at least 12 hours for later use;

S2. After fully mixing the PET resin, PBT resin, SEBS or SBS resin prepared in step S1, compatibilizer, antioxidant, lubricant, and pigment, extrude through twin-screw, draw strands, pelletize, and dry Instantly.

Compared with the prior art, the present invention has the following beneficial effects:

At present, the flow effect is implemented by using the melting point of the masterbatch base material which is higher than the melting point of the plastic base material to be injected. The single processing temperature of the masterbatch is close to or slightly higher than the plastic base material. Immersed in the background color of plastic products, a single color masterbatch with too high processing temperature will cause the color masterbatch to be difficult to melt and flow lines to be unnatural. The melting point of PET is close to the middle, and plasticized SEBS and SBS are introduced at the same time. Since the fluidity of SEBS and SBS is less affected by temperature, the plastic base material and flow pattern masterbatch of PBT/PE have a wider processing temperature in the injection molding process. , making the flow effect more stable and natural.

detailed description

The present invention will be described in detail below in conjunction with examples. The following examples will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those skilled in the art can make some adjustments and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

Examples 1-12

Examples 1-12 relate to masterbatches suitable for injection molding flow lines of medium-temperature hard rubber plastics, and their composition is shown in Table 1.

Follow these steps when preparing:

(1) Pour SEBS or SBS into the mixer according to the proportion, while stirring, pour in the plasticizer, stir for 10-20 minutes, stir evenly and place it for at least 12 hours for later use;

(2) Pour PET resin, PBT resin, oil-extended SEBS or SBS prepared in step (1), compatibilizer, antioxidant, lubricant, pigment into the agitator and mix thoroughly, then extrude through twin-screw , drawing, pelletizing, and drying to prepare the masterbatch suitable for injection molding of medium-temperature hard rubber plastics with flow pattern effect. The temperature of each section of the twin-screw extruder body is 20°C, 230°C, 240°C, 250°C, and the head temperature is 255°C; the screw speed of the extruder is 500 rpm.

Table 1, embodiment 1～12 formula

In Table 1, the viscosity of PET resin is 0.85dl/g, and the viscosity of PBT is 1.0dl/g;

The styrene content of SEBS1 is 28%, and the viscosity measured in 10wt% toluene solution at 25°C is 1300-2800cps;

The styrene content of SEBS2 is 32%, and the viscosity measured in 10wt% toluene solution at 25°C is 2800-5000cps;

The styrene content of SBS is 28%, and the viscosity measured in 10wt% toluene solution at 25°C is 1300-2800cps;

The compatibilizer is SEBS grafted maleic anhydride (SEBS-g-MAH);

The antioxidant is a compound of 1076 and 1068;

The lubricant is zinc stearate;

Pigment is carbon black, but not limited to carbon black, it can be other color pigments.

Examples 13-21

Embodiment 13, differs from Example 3 in that 33 parts of plasticizer are added, and the plasticizer is saturated linear naphthenic white oil;

Embodiment 14, differs from Example 3 in that 33 parts of plasticizer are added, and the plasticizer is aromatic base white oil;

Embodiment 15, differs from Example 3 in that 33 parts of plasticizer are added, and the plasticizer is paraffin-based white oil;

Embodiment 16, differs from Example 3 in that 132 parts of plasticizer are added, and the plasticizer is saturated linear naphthenic white oil;

Example 17, the difference from Example 3 is that the compatibilizer is selected SEBS grafted glycidyl methacrylate (SEBS-g-GMA);

Embodiment 18, the difference with embodiment 3 is that antioxidant selects antioxidant 1010, antioxidant 168 for use, wherein the number of parts is respectively 0.3 parts

Embodiment 19, differs from Embodiment 3 in that the antioxidant 1010 is increased, wherein the number of parts is 0.3 parts;

Embodiment 20, differs from Embodiment 3 in that the lubricant is selected from EBS;

Example 21 is different from Example 3 in that the lubricant is silicone powder.

Comparative example 1-5

Comparative Example 1 is different from Example 1 in that the prepared rhytogenic masterbatch only has 100 parts of PBT, no PET, oil-extended SEBS or SBS and compatibilizer.

Comparative Example 2 differs from Example 1 in that the rhylotype masterbatch prepared has only 100 parts of PET, without PET, oil-extended SEBS or SBS and compatibilizer.

Comparative Example 3 differs from Example 1 in that 18 parts of PBT and 2 parts of PET are prepared, and the rest of the composition and dosage are the same as in Example 1.

Comparative Example 4 differs from Example 1 in that the rhylotype masterbatch prepared consists of 2 parts of PBT and 18 parts of PET, and the rest of the composition and dosage are the same as in Example 1.

Comparative Example 5, the only difference from Example 7 is: no oil-extended SEBS or SBS was added.

The flow effect masterbatches of the above-mentioned examples and comparative examples were added to white ABS injection molded parts at 2wt.%, and performance tests were carried out. Specific steps are as follows:

(1) Using ABS, HIPS, AS, PA6, etc. of different background colors and their alloys as base materials, the embodiment takes white ABS as an example, mix the natural color ABS with 1% titanium dioxide pigment according to the mass fraction of ABS, pour it into the mixture and stir After being fully mixed with the machine, it is extruded through twin-screw, stranding, pelletizing, and drying. The screw speed is 500 rpm, the extrusion temperature is 190°C, 200°C, 210°C, 220°C, and the head temperature is 220°C.

(2) put into injection molding machine and carry out injection molding after mixing the rhyloline effect master batch of each embodiment and comparative example after drying and the white ABS prepared by step (1) respectively, and the number of rhyloline master batches can be based on actual conditions How much the flow pattern appears is weighed. For the comparison of the experiment, the addition amount of the flow pattern masterbatch in the implementation case is 2% of the white ABS base material. Two different injection molding temperatures are set for performance comparison: (1) Injection molding machine The set temperature is 210°C, 220°C, 230°C, 235°C; (2) The set temperature of the injection molding machine is 240°C, 250°C, 250°C, 265°C. The other process parameters are the same: the plasticizing back pressure is 0.3Mpa, the injection pressure is 20Mpa for the first stage, 30Mpa for the second stage, 40Mpa for the third stage, and the pressure holding and cooling time is 8s.

The properties of parts injection-molded by two different injection molding temperatures are compared by the appearance inspection of "the flow pattern masterbatch is not melted, the flow pattern masterbatch is completely melted and immersed in the substrate, and the flow pattern effect". The results are shown in Table 2:

Table 2

Among them, the unmelted flow pattern masterbatch means: the flow pattern masterbatch is agglomerated on the surface of the base material with relatively large particles;

The complete melting of the rhyolite masterbatch into the base material means that the rhyolite masterbatch cannot be seen at all, and it is completely melted into the base material, which has a significant impact on the base color of the base material.

Good flow effect means: the flow pattern masterbatch is naturally distributed on the surface of the base material, there are no larger particles or agglomeration on the surface of the base material, and at the same time the flow pattern masterbatch is not completely melted into the base material, resulting in a base color Obvious changes; good means: between good and poor flow pattern effect; poor flow pattern effect means: the flow pattern masterbatch is agglomerated on the surface of the base material with relatively large particles, or the flow pattern masterbatch is completely invisible It is found that it will be completely melted into the base material, which will have a significant impact on the base color of the base material.

The above descriptions are only preferred implementations of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principles of the present invention should also be regarded as the protection scope of the present invention.

Claims (10)

1. A kind of masterbatch that is applicable to the injection molding flow pattern of medium-temperature hard rubber type plastics, it is characterized in that, described masterbatch comprises the raw material composition of following parts by weight:

2. The masterbatch suitable for injection molding of medium-temperature hard rubber plastics according to claim 1, wherein said medium-temperature hard rubber plastics refer to ABS, HIPS, AS, PA6 and alloys thereof. 3. The masterbatch suitable for injection molding of medium-temperature hard rubber plastics according to claim 1, wherein the viscosity of the PET resin and PBT resin is greater than 0.8dl/g. 4. The masterbatch suitable for injection molding flow lines of medium-temperature hard rubber plastics according to claim 1, wherein the mass ratio of the PET and PBT resins is between 3:7 and 7:3. 5. according to claim 1, be applicable to the masterbatch that is suitable for the injection molding flow pattern of medium-temperature hard rubber type plastics, it is characterized in that, described SEBS or SBS resin is medium, high molecular weight one or two kinds, and its styrene content is 28-32%, at 25°C, the viscosity measured in 10wt% toluene solution is 1300-5000cps. 6. The masterbatch suitable for injection molding of medium-temperature hard rubber plastics according to claim 1, wherein the plasticizer is saturated straight-chain naphthenic white oil, aromatic white oil and paraffin-based white oil One of the oils. 7. The masterbatch suitable for injection molding flow lines of medium-temperature hard rubber plastics according to claim 1, wherein the compatibilizer is SEBS-g-MAH, SBS-g-MAH, SEBS-g- At least one of GMA and SBS-g-GMA. 8. The masterbatch suitable for injection molding flow lines of medium-temperature hard rubber plastics according to claim 1, wherein the antioxidant is one of antioxidant 1010, antioxidant 1076, and antioxidant 168. species or two or more. 9. The masterbatch suitable for injection molding of medium-temperature hard rubber plastics according to claim 1, wherein the lubricant is one or more of stearate, EBS, and silicone. 10. A preparation method suitable for injection molding of medium-temperature hard rubber plastics according to any one of claims 1-9, wherein the method comprises the following steps: S1. Under the condition of stirring, pour the plasticizer into SEBS or SBS resin; stir for 10-20 minutes, stir well and place it for at least 12 hours for later use; S2. After fully mixing the PET resin, PBT resin, SEBS or SBS resin prepared in step S1, compatibilizer, antioxidant, lubricant, and pigment, extrude through twin-screw, draw strands, pelletize, and dry Instantly.