阅读说明：本技术 一种低口模料渣堆积的tpv材料的制备方法 (Preparation method of TPV (thermoplastic vulcanizate) material with low die slag accumulation ) 是由 张泽峰 *** 于 2020-04-29 设计创作，主要内容包括：本发明涉及一种低口模料渣堆积的TPV材料的制备方法,属于高分子材料技术领域。本发明低口模料渣堆积的TPV材料的制备方法具有如下步骤：制备半成品母粒：将PP、EPDM、填料、润滑剂、相容剂喂入第一双螺杆挤出机,将加热后的填充油持续注入双螺杆挤出机的螺杆中,进行挤出造粒,然后切粒,制成半成品母粒；制备硫化母粒：将半成品母粒和硫化剂混合后喂入第二双螺杆挤出机,进行动态硫化,然后切粒,制成硫化母粒；制备成品粒子：将硫化母粒和其他助剂混合后喂入第二双螺杆挤出机中,继续进行动态硫化,然后切粒,制成成品粒子。本发明的方法能够显著减少TPV材料制备过程中的料渣堆积。(The invention relates to a preparation method of a TPV material with low die slag accumulation, belonging to the technical field of high polymer materials. The preparation method of the TPV material with the low die slag accumulation comprises the following steps: preparing a semi-finished master batch: feeding PP, EPDM, a filler, a lubricant and a compatilizer into a first double-screw extruder, continuously injecting heated filling oil into a screw of the double-screw extruder, carrying out extrusion granulation, and then carrying out granulation to prepare semi-finished master batches; preparing a vulcanized master batch: mixing the semi-finished master batch and a vulcanizing agent, feeding the mixture into a second double-screw extruder, carrying out dynamic vulcanization, and then carrying out grain cutting to prepare vulcanized master batches; preparing finished particles: and mixing the vulcanized master batch with other additives, feeding the mixture into a second double-screw extruder, continuously carrying out dynamic vulcanization, and then carrying out grain cutting to prepare finished product particles. The method can obviously reduce the material slag accumulation in the TPV material preparation process.)

1. The preparation method of the TPV material with the low die slag accumulation is characterized by comprising the following steps:

s1, preparing a semi-finished master batch: feeding PP, EPDM, a filler, a lubricant and a compatilizer into a first double-screw extruder, continuously injecting heated filling oil into a screw of the double-screw extruder, carrying out extrusion granulation, and then carrying out granulation to prepare semi-finished master batches;

s2, preparing vulcanized master batch: mixing the semi-finished master batch and a vulcanizing agent, feeding the mixture into a second double-screw extruder, carrying out dynamic vulcanization, and then carrying out grain cutting to prepare vulcanized master batches;

s3, preparing finished particles: and mixing the vulcanized master batch with other additives, feeding the mixture into a second double-screw extruder, continuously carrying out dynamic vulcanization, and then carrying out grain cutting to prepare finished product particles.

2. The method for preparing a TPV material with low die slag accumulation as claimed in claim 1, wherein the PP is subjected to fluorination treatment in step S1.

3. The method for preparing TPV material with low die slag accumulation according to claim 2, wherein the fluorination treatment is carried out by a plasma surface treatment method, and the working gas of the plasma surface treatment is CF₄And Ar.

4. The method for preparing the TPV material stacked by the low-die material slag according to claim 1, wherein the semi-finished master batch in the step S1 comprises the following raw material components in percentage by weight:

the compatilizer is polypropylene grafted maleic anhydride (PP-G-MAH).

5. The method for preparing a TPV material with low die slag buildup as claimed in claim 1, wherein the lubricant is hydroxyethylethylene bis stearamide (HEEBS) in step S1.

6. The method for preparing TPV material stacked by low die slag according to claim 1, wherein the weight percentages of the raw material components of the vulcanized master batch, namely the semi-finished master batch and the vulcanizing agent in step S1 are respectively 90-95% and 1-10%.

7. The method of preparing a TPV material with low die slag buildup as claimed in claim 1, wherein the length to diameter ratio of the screw of the first twin-screw extruder in step S1 is 80-100, and the length to diameter ratio of the screw of the second twin-screw extruder in steps S2 and S3 is 40-60.

8. The method for preparing TPV material with low die material slag accumulation as claimed in claim 1, wherein the host rotation speed of the twin-screw extruder during the dynamic vulcanization in step S2 is 200-400 r/min, the melting temperature is 250-300 ℃, and the time for dynamic vulcanization is 10-20 min; the rotation speed of the main machine of the twin-screw extruder is 200-400 r/min, the melting temperature is 250-300 ℃ and the dynamic vulcanization time is 10-20 min when the dynamic vulcanization is continuously carried out in the step S3.

Technical Field

The invention belongs to the technical field of high polymer materials, and relates to a preparation method of a TPV material with low die material slag accumulation.

Background

TPV (thermoplastic vulcanizer) thermoplastic vulcanized rubber, also called polyolefin alloy thermoplastic elastomer, has the elasticity and rebound shrinkage of rubber, excellent permanent deformation resistance, temperature resistance of the thermoplastic elastomer, wide hardness range, excellent electrical insulation, aging resistance and oil and solvent resistance, convenient processing, good hand feeling and easy coloring, and is widely applied to the fields of automobiles, toys, electronic products, building materials and the like. The TPV material is generally processed and formed by an extruder and has the advantages of high efficiency, continuity, universality and the like, but the TPV material often has the phenomenon of die material slag accumulation in the extrusion forming stage, and the accumulated material slag can be adhered to the surface of a product, so that the quality of the product is influenced.

The problem of die material slag accumulation when a TPV material is extruded at present is solved, and two types of modes are generally adopted: adjustment of the extrusion process or improvement of the properties of the TPV material itself. The general method for adjusting the extrusion process is to reduce the temperature of the mouth mold and install a flat-head air gun at the mouth mold to clean the slag; the method for improving the performance of the TPV material is to add a silicone master batch lubricant during the preparation of the TPV material, so that the friction of an extrusion die to the TPV material is reduced, and the phenomenon of slag accumulation is improved. However, the two conventional methods do not significantly improve the die slag accumulation phenomenon, and the quality of the product is also reduced.

Disclosure of Invention

The invention aims to provide a preparation method of a TPV material with low die material residue accumulation, aiming at solving the problem of product scrap caused by die material residue accumulation in the extrusion processing of the TPV material in the prior art.

The purpose of the invention can be realized by the following technical scheme:

a preparation method of TPV material with low die slag accumulation comprises the following steps:

s1, preparing a semi-finished master batch: feeding PP, EPDM, a filler, a lubricant and a compatilizer into a first double-screw extruder, continuously injecting heated filling oil into a screw of the double-screw extruder, carrying out extrusion granulation, and then carrying out granulation to prepare semi-finished master batches;

s2, preparing vulcanized master batch: mixing the semi-finished master batch and a vulcanizing agent, feeding the mixture into a second double-screw extruder, carrying out dynamic vulcanization, and then carrying out grain cutting to prepare vulcanized master batches;

s3, preparing finished particles: and mixing the vulcanized master batch with other additives, feeding the mixture into a second double-screw extruder, continuously carrying out dynamic vulcanization, and then carrying out grain cutting to prepare finished product particles.

The preparation method of the TPV material enables the vulcanization and plasticization of the TPV material to be more sufficient, so that the tendency of separating low-molecular-weight polymer components from a melt is reduced, and the material slag accumulation of a mouth mold in the preparation process of the TPV material is further reduced.

Preferably, the PP is subjected to a fluorination treatment in step S1.

According to the invention, the PP is subjected to fluorination treatment, fluorine is introduced into the surface of the PP to form a C-F bond, and the C-F bond exists in the form of fluorine grafted carbon element, so that the apparent viscosity of the PP can be obviously reduced, the lubricating property of the PP is improved, the extrusion pressure is reduced, further die material slag accumulation in the preparation process of the TPV material can be reduced, and the surface smoothness of a TPV product can be improved.

Preferably, the fluorination treatment is carried out by a method of plasma surface treatment of a working gasIs CF₄And Ar.

Preferably, the gas flow rate of the working gas is 2-5L/min.

Preferably, the voltage of the plasma surface treatment is 13-16kV, and the repetition frequency is 400-600 Hz.

According to the invention, the PP is subjected to fluorination treatment through plasma surface treatment, and fluorine is introduced to the surface of the PP, so that the wettability of the PP and the bonding property with EPDM are greatly enhanced. The plasma treatment method is convenient and fast, avoids the use of chemical reagents and the generation of various side reactions, and is green and environment-friendly.

Preferably, in the step S1, the semi-finished master batch comprises the following raw material components in percentage by weight:

the compatilizer is polypropylene grafted maleic anhydride (PP-G-MAH).

The invention selects the Ethylene Propylene Diene Monomer (EPDM) and the PP to blend to prepare the TPV material, the EPDM and the PP have similar solubility parameters and surface tension values, and the EPDM and the PP can be considered to have certain compatibility and can play a better role in compatibility and toughening when blended. Meanwhile, the compatilizer PP-G-MAH is added into the formula system, so that various components in the TPV material are further integrally and closely combined, the tendency of separating low molecular weight polymer components from a melt is reduced, the TPV material is not subjected to material slag in friction with a die during extrusion molding, and the phenomenon of die material slag accumulation is improved.

Further preferably, in step S1, the semi-finished master batch comprises the following raw material components in percentage by weight:

preferably, the filler in step S1 is one or more of talc, calcium carbonate, clay, silica, and titanium dioxide.

Further preferably, the filler in step S1 is talc.

Preferably, the lubricant in step S1 is hydroxyethyl ethylene bis stearamide (HEEBS).

Preferably, the extender oil in step S1 is one or more of naphthenic oil, paraffin oil, aromatic oil, and white mineral oil.

Preferably, the vulcanizing agent in step S2 is a peroxide initiator.

Further preferably, the vulcanizing agent in step S2 is benzoyl peroxide, benzoyl tert-butyl peroxide or methyl ethyl ketone peroxide.

Preferably, the raw material components of the vulcanized master batch in the step S2 comprise 90-95 wt% of the master batch and 1-10 wt% of the vulcanizing agent.

Further preferably, the raw material components of the vulcanized master batch in step S2 comprise the semi-finished master batch and the vulcanizing agent in a weight percentage of 90% and 10%, respectively.

Preferably, the length-diameter ratio of the screw of the first twin-screw extruder in the step S1 is 80-100, and the length-diameter ratio of the screw of the second twin-screw extruder in the steps S2 and S3 is 40-60.

Preferably, the other auxiliary agents in the step S3 comprise an antioxidant and a color master, wherein the antioxidant is a hindered phenol antioxidant irganox1010, irganox1076 or irganox 1790.

Preferably, the weight percentages of the vulcanized master batch, the antioxidant and the master batch of the finished product particles in the step S3 are respectively 90-95%, 1-5% and 1-5%.

Further preferably, the weight percentages of the vulcanized master batch, the antioxidant and the master batch of the finished product particles in the step S3 are respectively 90%, 5% and 5%.

Preferably, the main machine rotation speed of the twin-screw extruder during the dynamic vulcanization in the step S2 is 200-400 r/min, the melting temperature is 250-300 ℃, and the time of the dynamic vulcanization is 10-20 min; the rotation speed of the main machine of the twin-screw extruder is 200-400 r/min, the melting temperature is 250-300 ℃ and the dynamic vulcanization time is 10-20 min when the dynamic vulcanization is continuously carried out in the step S3.

Preferably, the dicing in step S1, step S2, and step S3 is performed using an underwater dicing apparatus.

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

(1) according to the invention, the preparation method of the TPV material is improved, so that the TPV material is more fully vulcanized and plasticized, the tendency of separating a low-molecular-weight polymer component from a melt is reduced, and the die material slag accumulation condition in the preparation process of the TPV material is further reduced;

(2) according to the invention, the matrix PP of the TPV material is subjected to fluorination treatment, so that the polarity and the lubricating property of the PP are improved, the extrusion pressure is reduced, and the die material slag accumulation condition in the preparation process of the TPV material is reduced;

(3) according to the invention, the fluorination treatment is carried out on PP through the plasma surface treatment, so that the method is convenient and fast, and the use of chemical reagents and the generation of various side reactions are avoided;

(4) the compatilizer PP-G-MAH is added into the formula system of the TPV material, so that various components in the TPV material further form an integral and close combination, and the phenomenon of die material slag accumulation is improved;

(5) the TPV material prepared by the invention has excellent performance, and is particularly suitable for preparing automobile parts.

Detailed Description

The following are specific examples of the present invention and further describe the technical solutions of the present invention, but the present invention is not limited to these examples.