Processing Aid for Anti-Spray Frost Rubber and Its Preparation Method

Abstract

The present invention discloses a processing aid for anti-blooming rubber and a preparation method thereof, belonging to the technical field of rubber auxiliaries. The processing aid, calculated by weight percentage, comprises 40 parts - 50 parts of di-tert-butyl peroxycumene, 40 parts - 45 parts of calcium carbonate, 5 parts - 15 parts of other inorganic inert materials, and 5 parts - 10 parts of an anti-blooming aid; the anti-blooming aid is obtained by an epoxy ring-opening reaction of an amino-terminated hyperbranched polyamide and an unsaturated glycidyl ester. The processing aid for anti-blooming rubber prepared by the present invention solves the problem that blooming easily occurs when BIPB is added to rubber materials. The processing aid in the present invention includes a self-made anti-blooming aid, which is obtained by an epoxy ring-opening reaction of an amino-terminated hyperbranched polyamide and an unsaturated glycidyl ester, and has both good dispersion performance and adsorption performance, and can inhibit the problem that blooming easily occurs in rubber materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of rubber auxiliaries, and particularly relates to a processing aid for anti-blooming rubber and a preparation method thereof. Background Art

[0002] Rubber blooming includes blooming on the surface of the rubber compound and blooming on the surface of the product. Blooming is a phenomenon in which liquid or solid compounding agents migrate from the inside of the rubber to the surface of the rubber. The main reasons for blooming are the supersaturation of compounding agents in the rubber compound or some incompatible compounds with smaller molecular weights.

[0003] Di-tert-butyl peroxyisopropylbenzene, commonly known as BIPB or "odorless DCP". Due to its bifunctional group and high active oxygen content, the crosslinking efficiency of BIPB is relatively high. Under the same crosslinking effect, the addition amount is about 2 / 3 of that of ordinary DCP (dicumyl peroxide), and the pungent odor during the operation process and in the manufactured products is small. It is commonly used as a crosslinking agent for plastics and rubbers such as chlorinated polyethylene, ethylene-propylene-diene monomer rubber, ethylene-vinyl acetate copolymer, silicone rubber, and nitrile rubber. The main disadvantage of BIPB is that it is prone to cause the blooming problem of products. The main reason for blooming is that the decomposition product of BIPB, dihydroxy-1,4-diisopropylbenzene, has low solubility in some rubbers, and the blooming formed is mostly white or dark white needle-shaped crystals.

[0004] Blooming on the rubber surface will affect the appearance quality and decorative performance of the rubber, and blooming will reduce the surface viscosity of the rubber compound during calendering, resulting in scorching of the rubber compound and aging of the product. Blooming of rubber products not only seriously affects the appearance quality of the products, but also affects the service performance and life of rubber products to a certain extent, and also affects the processing performance and physical and mechanical properties of the rubber compound. Summary of the Invention

[0005] The purpose of the present invention is to provide a processing aid for anti-blooming rubber and a preparation method thereof to solve the problem that blooming is likely to occur when BIPB is added to rubber materials.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A processing aid for anti-blooming rubber, calculated by weight percentage, includes 40 parts - 50 parts of di-tert-butyl peroxyisopropylbenzene, 40 parts - 45 parts of calcium carbonate, 5 parts - 15 parts of other inorganic inert materials, and 5 parts - 10 parts of anti-blooming agent; the anti-blooming agent is obtained by an epoxy ring-opening reaction of terminal amino hyperbranched polyamide and unsaturated glycidyl ester.

[0008] Further, the anti-blooming agent is prepared by the following steps:

[0009] The amino-terminated hyperbranched polyamide and unsaturated glycidyl ester are added to toluene, ultrasonically dispersed, heated to 80 °C and refluxed. After the reaction is completed, the solvent is removed to obtain the anti-blooming aid.

[0010] Furthermore, the dosage ratio of the amino-terminated hyperbranched polyamide to the unsaturated glycidyl ester is 50 g: 0.01 - 0.02 mol; the molecular weight of the amino-terminated hyperbranched polyamide is 800 - 5600. Different types of anti-blooming aids can be prepared by adjusting the raw material ratio of the amino-terminated hyperbranched polyamide and the unsaturated glycidyl ester to improve the dispersion effect of the anti-blooming aid in the material. The addition amount of the unsaturated glycidyl ester should not be too much, as excessive addition will lead to too high a vulcanization crosslinking density, resulting in poor ductility of the rubber material. Within the dosage ratio range of 50 g: 0.01 - 0.02 mol, not only can the cost be reduced, but also the subsequent processing process is facilitated.

[0011] Furthermore, the amino-terminated hyperbranched polyamide is one of amino-terminated hyperbranched polyamide Hyper N101, amino-terminated hyperbranched polyamide Hyper N102, and amino-terminated hyperbranched polyamide Hyper N103.

[0012] Furthermore, the unsaturated glycidyl ester is one of glycidyl methacrylate and allyl glycidyl ether.

[0013] Furthermore, the other inorganic inert materials are at least one of nano-silica, nano-zinc oxide, and nano-titanium dioxide. The other inorganic inert materials are adjusted according to the application scenario.

[0014] Furthermore, the other inorganic inert materials are modified with vinyl silane coupling agent. After modification, the dispersion performance can be improved to prepare rubber materials with higher requirements.

[0015] Furthermore, the steps of modifying with vinyl silane coupling agent are as follows:

[0016] The other inorganic inert materials are added to toluene, ultrasonically dispersed, and then vinyl silane coupling agent is added. The addition amount of vinyl silane coupling agent is 4% of the mass of the other inorganic inert materials. The temperature is raised for reflux reaction for 2 h. After the reaction is completed, washing and drying are carried out.

[0017] A preparation method of a processing aid for anti-blooming rubber includes the following steps:

[0018] Calcium carbonate, other inorganic inert materials, anti-blooming additives and copolymers are blended, and then di-tert-butyl peroxide cumene is added and mixed evenly, extruded, cooled and pelletized to obtain a processing aid for anti-blooming rubber. During the processing, friction occurs during the blending of raw materials, which may lead to too high reaction temperature. The added anti-blooming additives are beneficial to reducing the mixing time and better mixing the materials within the limited dispersion time. After mixing, di-tert-butyl peroxide cumene is added for mixing to avoid premature crosslinking and improve the stability of the product.

[0019] Furthermore, the copolymer is selected from one of ethylene-vinyl acetate copolymer; copolymer of ethylene and acrylate; styrene-ethylene-butene hydrogenated copolymer and styrene-ethylene-propylene hydrogenated copolymer.

[0020] Advantages of the present invention:

[0021] The present invention prepares a processing aid for anti-blooming rubber, which solves the problem that blooming is likely to occur when BIPB is added to rubber materials. The processing aid in the present invention includes a self-made anti-blooming additive, which is obtained by the ring-opening reaction of terminal amino hyperbranched polyamide and unsaturated glycidyl ester, and has both good dispersion performance and adsorption performance, and can inhibit the problem that rubber materials are prone to blooming.

[0022] The structure of the anti-blooming additive in the present invention retains the branched structure in the structure of terminal amino hyperbranched polyamide, reduces the system viscosity and improves the dispersion effect. Moreover, the cavity formed by the branched structure has good adsorption performance and has a strong adsorption force on the decomposed small molecule substances, and can inhibit the migration of decomposed dihydroxy-1,4-diisopropylbenzene in rubber materials. The anti-blooming additive in the present invention further increases the molecular weight by reacting with unsaturated glycidyl ester, and at the same time introduces a double bond structure, which provides reaction sites for co-vulcanization with rubber and further improves the migration resistance of the anti-blooming additive, preventing the formation of a continuous migration layer, which can not only eliminate the aggregation phenomenon, but also improve the anti-blooming performance.

[0023] To further improve the performance of the processing aid for anti-blooming rubber, the added other inert materials can also be treated to improve the dispersibility of other inert materials and enhance the dispersion effect of other inert materials in the processing aid for anti-blooming rubber, and can also improve the overall performance after rubber crosslinking. Specific embodiments

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0025] Example 1

[0026] A processing aid for anti-blooming rubber:

[0027] Add the amino-terminated hyperbranched polyamide Hyper N101 (molecular weight 800 - 1000) and glycidyl methacrylate into toluene, disperse ultrasonically, heat to 80 °C and reflux for reaction. After the reaction is completed, remove the solvent to obtain the anti-blooming aid; among them, the dosage ratio of the amino-terminated hyperbranched polyamide to glycidyl methacrylate is 50 g: 0.01 mol.

[0028] By weight, blend 40 - 45 parts of calcium carbonate, 5 - 15 parts of nano-silica, 5 - 10 parts of the prepared anti-blooming aid with 50 parts of ethylene-vinyl acetate copolymer (Elvax 360A), then add 40 - 50 parts of di-tert-butyl peroxycumene and mix evenly, then extrude, and prepare using a barrel temperature of 75 °C and a screw speed of 100 rpm. After extrusion, cool the produced material and cut it into particles to obtain a processing aid for anti-blooming rubber.

[0029] Examples 2 - 5

[0030] This example is different from Example 1 in that the raw material ratio is adjusted, and the remaining raw materials and preparation process are the same as those in Example 1.

[0031] Table 1

[0032]

[0033]

[0034] Example 6

[0035] This example is different from Example 1 in that the anti-blooming aid is different. Specifically:

[0036] Replace the amino-terminated hyperbranched polyamide Hyper N101 (molecular weight 800 - 1000) with the amino-terminated hyperbranched polyamide Hyper N102 (molecular weight 1900 - 2200), and the remaining raw materials and preparation process are the same as those in Example 1.

[0037] Example 7

[0038] This example is different from Example 1 in that the anti-blooming aid is different. Specifically:

[0039] Replace the hyperbranched polyamide with terminal amino groups Hyper N101 (molecular weight 800 - 1000) with hyperbranched polyamide with terminal amino groups Hyper N103 (molecular weight 5200 - 5600). The dosage ratio of the hyperbranched polyamide with terminal amino groups to glycidyl methacrylate is 50 g : 0.02 mol. The other raw materials and the preparation process are the same as those in Example 1.

[0040] Example 8

[0041] The difference between this example and Example 1 lies in different other inorganic inert materials. Specifically:

[0042] The nano-silica is modified with vinyl silane coupling agent. The modification steps are as follows:

[0043] Add the nano-silica into toluene, add vinyl silane coupling agent (KH-570) after ultrasonic dispersion. The addition amount of the vinyl silane coupling agent is 4% of the mass of the nano-silica. Heat up to reflux for 2 h. After the reaction ends, wash and dry to obtain. The other raw materials and the preparation process are the same as those in Example 1.

[0044] Comparative Example 1

[0045] Compared with Example 1, in this comparative example, the anti-blooming aid is replaced with stearic acid, and the other raw materials and the preparation process remain unchanged.

[0046] Record the mixing time (mixing time for visual complete dispersion) of the materials in Example 1 - Example 8 and Comparative Example 1. The results are shown in Table 2 below:

[0047] Table 2

[0048] Project Mixing time Example 1 Less than 2 min Example 2 Less than 2 min Example 2 Less than 2 min Example 3 Less than 2 min Example 4 Less than 2 min Example 5 Less than 2 min Example 6 Less than 2 min Example 7 Less than 2 min Example 8 Less than 2 min Comparative Example 1 Greater than 5 min

[0049] The anti-blooming aid prepared by the present invention

[0050] Test the prepared auxiliary samples in Example 1 - Example 8 and Comparative Example 1 to prepare the samples to be tested; the formula of the sample to be tested is 100 parts of EPDM, 140 parts of carbon black (70 parts of N-550 and 70 parts of N-772), 50 parts of paraffin oil (SUNPAR 2280) and 9 parts of the processing aid for anti-blooming rubber prepared in Example 1 - Example 8.

[0051] Test the mechanical properties according to the standard GB / T528 - 2009; blooming test: Turn on the switch of the constant temperature and humidity chamber, set the temperature to 70 °C and the humidity to 95%. After the temperature and humidity reach the set values, put the sample into the constant temperature and humidity chamber. Start the blooming test, and the test time is 168 hours (i.e., 7 days). After the test time ends, take out the sample and observe the change of the sample surface. Each group of samples is tested three times. The results are shown in Table 3 below:

[0052] Table 3

[0053]

[0054]

[0055] It can be seen from the test results that a processing aid for anti-blooming rubber prepared by the present invention not only has a good effect of avoiding blooming. Stearic acid added in Comparative Example 1 is also commonly used as an additive to reduce rubber blooming, but its improvement effect is limited. An appropriate increase in the amount of stearic acid can dissolve or increase the solubility of inorganic substances in rubber, indirectly preventing whitening. However, if the addition amount is too much, it is likely to spray out by itself. In the present invention, the anti-blooming aid has stronger migration resistance and a wider range of addition amounts (i.e., the amount is easier to control). Moreover, under the same ratio conditions, the mechanical property indexes are improved, achieving the effects of saving materials and reducing costs.

[0056] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0057] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A processing aid for anti-spray frost rubber, characterized in that, By weight parts, it includes 40-50 parts of di-tert-butyl peroxyisopropylbenzene, 40-45 parts of calcium carbonate, 5-15 parts of other inorganic inert materials, 5-10 parts of anti-blooming agent, and 50 parts of copolymer; the anti-blooming agent is obtained by the epoxy ring-opening reaction of terminal amino hyperbranched polyamide and unsaturated glycidyl ester; the copolymer is selected from one of ethylene-vinyl acetate copolymer; copolymer of ethylene and acrylate; hydrogenated styrene-ethylene-butene copolymer and hydrogenated styrene-ethylene-propylene copolymer.

2. The processing aid for anti-spraying frost rubber according to claim 1, characterized in that, The anti-blooming agent is prepared by the following steps: Add terminal amino hyperbranched polyamide and unsaturated glycidyl ester into a solvent, ultrasonically disperse, heat under reflux for reaction, after the reaction ends, remove the solvent to obtain the anti-blooming agent.

3. The processing aid for anti-spraying frost rubber according to claim 1, characterized in that, The dosage ratio of the terminal amino hyperbranched polyamide to the unsaturated glycidyl ester is 50 g: 0.01-0.02 mol; the molecular weight of the terminal amino hyperbranched polyamide is 800-5600.

4. The processing aid for anti-spraying frost rubber according to claim 1, characterized in that, The terminal amino hyperbranched polyamide is one of terminal amino hyperbranched polyamide Hyper N101, terminal amino hyperbranched polyamide Hyper N102, and terminal amino hyperbranched polyamide Hyper N103.

5. The processing aid for anti-spraying frost rubber according to claim 1, characterized in that, The unsaturated glycidyl ester is one of glycidyl methacrylate and allyl glycidyl ether.

6. The processing aid for anti-spraying frost rubber according to claim 1, characterized in that, The other inorganic inert materials are at least one of nano-silica, nano-zinc oxide, and nano-titanium dioxide.

7. The processing aid for anti-spraying frost rubber according to claim 1, wherein, The other inorganic inert materials are modified by vinyl silane coupling agent.

8. A processing aid for anti-spraying frost rubber according to claim 7, characterized in that, The steps of modification by vinyl silane coupling agent are as follows: add the other inorganic inert materials into toluene, ultrasonically disperse and then add vinyl silane coupling agent, the addition amount of vinyl silane coupling agent is 4% of the mass of the other inorganic inert materials, heat under reflux for reaction, after the reaction ends, wash and dry to obtain.

9. A preparation method of a processing aid for anti-spray frost rubber as described in any one of claims 1-8, characterized in that, It includes the following steps: Blend calcium carbonate, other inorganic inert materials, anti-blooming agent and copolymer, then add di-tert-butyl peroxyisopropylbenzene and mix evenly, extrude, cool and pelletize to obtain a processing aid for anti-blooming rubber.

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