阅读说明：本技术 一种天然胶的塑炼方法 (Plasticating method of natural rubber ) 是由 吴喜林 吕晓刚 朱秀祥 于 2020-12-11 设计创作，主要内容包括：本发明公开了一种天然胶的塑炼方法,其技术方案是：包括以下制备步骤：S1,将开炼机中的辊温和辊距进行设置；S2,将天然橡胶放入到开炼机中进行塑炼；S3,然后将酚醛树脂和耐磨剂依次放入到开炼机中进行塑炼,过后再加入防老剂进行塑炼,在塑炼的时候,需要多次对炼制的天然橡胶进行割刀以利于散热及获得均匀的可塑性,一种天然胶的塑炼方法有益效果是：通过在炼胶的时候加入合适比例的聚氨酯,大大的提高了天然橡胶的耐磨性,从而会提高天然橡胶的使用寿命,再通过加入合适比例的高苯乙烯,从而会提高天然橡胶的抗老性,以及再加入合适比例的酚醛树脂,提高了天然橡胶的硬度,从而会让天然橡胶软中带硬,提高适用性。(The invention discloses a plastication method of natural rubber, which adopts the technical scheme that: the preparation method comprises the following preparation steps: s1, setting the roller temperature and the roller spacing in the open mill; s2, placing the natural rubber into an open mill for plastication; s3, sequentially placing phenolic resin and a wear-resisting agent into an open mill for plastication, then adding an anti-aging agent for plastication, and during plastication, cutting a refined natural rubber for multiple times to facilitate heat dissipation and obtain uniform plasticity, wherein the plastication method of the natural rubber has the beneficial effects that: through adding the polyurethane of suitable proportion in the time of mixing rubber, great improvement natural rubber's wearability to can improve natural rubber's life, the rethread adds the high styrene of suitable proportion, thereby can improve natural rubber's ageing resistance, and add the phenolic resin of suitable proportion again, improved natural rubber's hardness, thereby can let the soft medium of natural rubber and hardness, improve the suitability.)

1. A plasticating method of natural rubber is characterized in that: the preparation method comprises the following preparation steps:

s1, setting the roll temperature and the roll spacing in the open mill, wherein the roll temperature is set to be 35-45 ℃, and the roll spacing is set to be 0.4-0.8 mm;

s2, putting 70g-120g of natural rubber into an open mill for plastication for 3-7 min;

s3, sequentially putting 4g-8g of phenolic resin and 2g-6g of wear-resisting agent into an open mill for plastication for 3-5min, then adding 5g-15g of anti-aging agent for plastication for 2-3min, wherein in the plastication, the refined natural rubber needs to be subjected to cutting knife for multiple times so as to be beneficial to heat dissipation and obtain uniform plasticity, and after the natural rubber is subjected to first thin-pass, the natural rubber needs to be added by twisting for 90 degrees for the second time;

s4, after the plastication is finished, putting the plasticated rubber material for the first time into an internal mixer for plastication for the second time, setting the temperature to be 140-150 ℃, and the plastication time to be 3-4min, then putting 10-30 g of zinc oxide, 4-8 g of vulcanizing agent, 5-20 g of olefin and 3-7 g of softener into the internal mixer for mixing, raising the temperature of the internal mixer to 170-180 ℃, and mixing for 4-5 min;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to be 55-65 ℃, the head temperature to be 75-85 ℃ and the mouth temperature to be 85-95 ℃ so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

2. A process for masticating natural rubber according to claim 1, wherein: in the above-mentioned S2, the natural rubber is cut into pieces of 2 to 6cm before being put into the open mill.

3. A process for masticating natural rubber according to claim 1, wherein: the feeding interval time of the phenolic resin and the wear-resisting agent in the S3 is 1-2 min.

4. A process for masticating natural rubber according to claim 1, wherein: in the S4, the first plasticated rubber is put into an internal mixer to be placed and cooled for 1-2 hours.

5. A process for masticating natural rubber according to claim 1, wherein: in the S4, the zinc oxide, the vulcanizing agent, the olefin and the softening agent are put into the internal mixer in the sequence that the zinc oxide and the vulcanizing agent are put into the internal mixer at an interval of 0.5-1min, and then the olefin and the softening agent are put into the internal mixer.

6. A process for masticating natural rubber according to claim 1, wherein: the vulcanizing agent is prepared from N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 1: 1 ratio of the components.

7. A process for masticating natural rubber according to claim 1, wherein: the wear-resisting agent is made of polyurethane.

8. A process for masticating natural rubber according to claim 1, wherein: the anti-aging agent is made of high styrene.

9. A process for masticating natural rubber according to claim 1, wherein: the softening agent is prepared from paraffin, asphalt and coal tar according to the weight ratio of 1: 1: 1, and (2) mixing the components in a ratio.

Technical Field

The invention relates to the technical field of natural rubber, in particular to a plastication method of natural rubber.

Background

The natural rubber is a natural high molecular compound taking polyisoprene as a main component, the molecular formula is (C5H8) n, 91-94% of the natural rubber is rubber hydrocarbon, and the balance is non-rubber substances such as protein, fatty acid, ash, saccharides and the like, the natural rubber is widely used general rubber, generally, the natural rubber is an elastic solid substance prepared by processing procedures such as solidification, drying and the like from natural latex collected from Brazilian rubber trees, is generally a flaky solid, has the relative density of 0.94, the refractive index of 1.522, the elastic film amount of 2-4 MPa, is softened at 130-140 ℃, is soft at 150-160 ℃, starts to degrade at 200 ℃, has higher elasticity at normal temperature and is slightly plastic, and is crystallized and hardened at low temperature. Has better alkali resistance but no strong acid resistance, is insoluble in water, lower ketone and alcohol, and can swell in nonpolar solvents such as trichloromethane, carbon tetrachloride and the like.

The prior art has the following defects: the existing natural rubber has poor effects on hardness, wear resistance and aging resistance, so that the application range of the natural rubber can be influenced.

Therefore, it is necessary to develop a method for plasticating natural rubber.

Disclosure of Invention

Therefore, the invention provides a plastication method of natural rubber, which comprises the steps of taking natural rubber as a main material, adding polyurethane in a proper proportion during rubber mixing, so that the wear resistance of the natural rubber can be improved, adding high styrene in a proper proportion, so that the anti-aging property of the natural rubber can be improved, and adding phenolic resin in a proper proportion, so that the hardness of the natural rubber can be improved, the natural rubber can be made soft and medium hard, the applicability is improved, and the problem that the application range of the existing natural rubber is limited is solved.

In order to achieve the above purpose, the invention provides the following technical scheme: the preparation method comprises the following preparation steps:

s1, setting the roll temperature and the roll spacing in the open mill, wherein the roll temperature is set to be 35-45 ℃, and the roll spacing is set to be 0.4-0.8 mm;

s2, putting 70g-120g of natural rubber into an open mill for plastication for 3-7 min;

s3, sequentially putting 4g-8g of phenolic resin and 2g-6g of wear-resisting agent into an open mill for plastication for 3-5min, then adding 5g-15g of anti-aging agent for plastication for 2-3min, wherein in the plastication, the refined natural rubber needs to be subjected to cutting knife for multiple times so as to be beneficial to heat dissipation and obtain uniform plasticity, and after the natural rubber is subjected to first thin-pass, the natural rubber needs to be added by twisting for 90 degrees for the second time;

s4, after the plastication is finished, putting the plasticated rubber material for the first time into an internal mixer for plastication for the second time, setting the temperature to be 140-150 ℃, and the plastication time to be 3-4min, then putting 10-30 g of zinc oxide, 4-8 g of vulcanizing agent, 5-20 g of olefin and 3-7 g of softener into the internal mixer for mixing, raising the temperature of the internal mixer to 170-180 ℃, and mixing for 4-5 min;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to be 55-65 ℃, the head temperature to be 75-85 ℃ and the mouth temperature to be 85-95 ℃ so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

Preferably, in the step S2, the natural rubber is cut into pieces of 2 to 6cm before being put into the open mill.

Preferably, the interval between the phenolic resin and the anti-wear agent in S3 is 1-2 min.

Preferably, in the step S4, the zinc oxide, the vulcanizing agent, the olefin and the softener are put into the internal mixer in sequence, wherein the zinc oxide and the vulcanizing agent are put into the internal mixer at an interval of 0.5-1min, and then the olefin and the softener are put into the internal mixer.

Preferably, the vulcanizing agent is prepared from N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 1: 1 ratio of the components.

Preferably, the material of the anti-wear agent is polyurethane.

Preferably, the material of the anti-aging agent is high styrene.

Preferably, the softening agent is prepared from paraffin, asphalt and coal tar according to the weight ratio of 1: 1: 1, and (2) mixing the components in a ratio.

The invention has the beneficial effects that:

according to the invention, natural rubber is selected as a main material, polyurethane with a proper proportion is added during rubber mixing, the wear resistance of the natural rubber is greatly improved, so that the service life of the natural rubber can be prolonged, the anti-aging property of the natural rubber can be improved by adding high styrene with a proper proportion, and the hardness of the natural rubber is improved by adding phenolic resin with a proper proportion, so that the natural rubber is soft and medium hard, and the applicability is improved.

Detailed Description

The following description of the preferred embodiments of the present invention is provided for the purpose of illustration and description, and is in no way intended to limit the invention.

Example 1:

the invention provides a plastication method of natural rubber, which comprises the following preparation steps:

s1, setting the roll temperature and the roll spacing in the open mill, wherein the roll temperature is set to be 35-45 ℃, and the roll spacing is set to be 0.4-0.8 mm;

s2, putting 70g-120g of natural rubber into an open mill for plastication, wherein the plastication time is 3-7min, and the natural rubber needs to be cut into blocks of 2-6cm before being put into the open mill;

s3, sequentially putting 4g-8g of phenolic resin and 2g-6g of wear-resistant agent into an open mill for plastication, wherein the plastication time is 3-5min, then adding 5g-15g of anti-aging agent for plastication, the plastication time is 2-3min, during the plastication, cutting knife is needed to be carried out on refined natural rubber for multiple times so as to be beneficial to heat dissipation and obtain uniform plasticity, and after the natural rubber is subjected to first thin-pass, the natural rubber is added by twisting 90 degrees for the second time, wherein the adding interval time of the phenolic resin and the wear-resistant agent is 1-2 min;

s4, after plastication is finished, putting the plasticated rubber material for the first time into an internal mixer for plastication for the second time, setting the temperature to be 140-150 ℃, and the plastication time to be 3-4min, then putting 10-30 g of zinc oxide, 4-8 g of vulcanizing agent, 5-20 g of olefin and 3-7 g of softening agent into the internal mixer for mixing, raising the temperature of the internal mixer to 170-180 ℃, and the mixing time to be 4-5min, putting the plasticated rubber material for the first time into the internal mixer, needing to be placed and cooled for 1-2h, putting the zinc oxide, the vulcanizing agent, the olefin and the softening agent into the internal mixer in the sequence that the zinc oxide and the vulcanizing agent are firstly put into the internal mixer, the interval is 0.5-1min, and then putting the olefin and the softening agent into the internal mixer;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to be 55-65 ℃, the head temperature to be 75-85 ℃ and the mouth temperature to be 85-95 ℃ so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

Further, the vulcanizing agent is prepared from N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 1: 1 ratio of the components.

Furthermore, the material of the wear-resisting agent is polyurethane.

Furthermore, the material of the anti-aging agent is high styrene.

Further, the softening agent is prepared from paraffin, asphalt and coal tar according to the weight ratio of 1: 1: 1, and (2) mixing the components in a ratio.

Example 2:

the invention provides a plastication method of natural rubber, which comprises the following preparation steps:

s1, setting the temperature in the internal mixer to 140 ℃;

s2, putting 70g of natural rubber into an internal mixer for primary plastication, wherein the plastication time is 3min, then putting 10g of zinc oxide, 4g of vulcanizing agent, 5g of olefin and 3g of softener into the internal mixer for mixing, raising the temperature of the internal mixer to 170 ℃, and keeping the mixing time to 4min, wherein the zinc oxide, the vulcanizing agent, the olefin and the softener are put into the internal mixer in the sequence that the zinc oxide is firstly put into the internal mixer at an interval of 0.5min, the vulcanizing agent, the olefin and the softener are then put into the internal mixer, and the natural rubber needs to be cut into blocks of 2cm before being put into an open mixer;

s3, placing the rubber material subjected to primary plastication into an open mill for secondary plastication, wherein the plastication time is 3min, the roller temperature is set at 35 ℃, the roller spacing is set at 0.4mm, and the rubber material subjected to primary plastication is placed into the open mill for cooling for 1 h;

s4, sequentially putting 4g of phenolic resin and 2g of wear-resisting agent into an open mill for plastication, wherein the plastication time is 3min, adding 5g of anti-aging agent for plastication after plastication, the plastication time is 2min, cutting the refined natural rubber for multiple times during plastication so as to be beneficial to heat dissipation and obtain uniform plasticity, twisting the natural rubber for 90 degrees for the second time after the natural rubber is subjected to first thin-pass, and the putting interval time of the phenolic resin and the wear-resisting agent is 1 min;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to be 55 ℃, the head temperature to be 75 ℃ and the mouth temperature to be 85 ℃, so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

Further, the vulcanizing agent is prepared from N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 1: 0.5 proportion.

Furthermore, the material of the wear-resisting agent is polyurethane.

Furthermore, the material of the anti-aging agent is high styrene.

Further, the softening agent is prepared from paraffin, asphalt and coal tar according to the weight ratio of 1: 0.5: 1, and (2) mixing the components in a ratio.

Example 3:

the invention provides a plastication method of natural rubber, which comprises the following preparation steps:

s1, setting the roll temperature and the roll spacing in the open mill, wherein the roll temperature is set at 40 ℃, and the roll spacing is set at 0.6 mm;

s2, putting 95g of natural rubber into an open mill for plastication, wherein the plastication time is 4.5min, and the natural rubber needs to be cut into 4cm blocks before being put into the open mill;

s3, sequentially putting 6g of phenolic resin and 4g of wear-resistant agent into an open mill for plastication, wherein the plastication time is 4min, adding 10g of anti-aging agent for plastication after plastication, the plastication time is 2.5min, cutting the refined natural rubber for multiple times during plastication so as to be beneficial to heat dissipation and obtain uniform plasticity, twisting the natural rubber for 90 degrees for the second time after the natural rubber is subjected to first thin-pass, and the putting interval time of the phenolic resin and the wear-resistant agent is 1.5 min;

s4, after plastication is finished, putting the plasticated rubber material for the first time into an internal mixer for plastication for the second time, setting the temperature to be 145 ℃, plasticating time to be 3.5min, then putting 20g of zinc oxide, 6g of vulcanizing agent, 12.5g of olefin and 5g of softener into the internal mixer for mixing, raising the temperature of the internal mixer to 175 ℃, mixing time to be 4.5min, putting the plasticated rubber material for the first time into the internal mixer, placing the plasticated rubber material for the first time into the internal mixer for cooling for 1.5h, putting the zinc oxide, the vulcanizing agent, the olefin and the softener into the internal mixer in the sequence that the zinc oxide, the vulcanizing agent and the olefin are firstly put into the internal mixer at intervals of 0.5min, and then putting the softener into the internal mixer;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to be 60 ℃, the head temperature to be 80 ℃ and the mouth temperature to be 90 ℃, so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

Further, the vulcanizing agent is prepared by mixing N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 0.4: 1 ratio of the components.

Furthermore, the material of the wear-resisting agent is polyurethane.

Furthermore, the material of the anti-aging agent is high styrene.

Further, the softening agent is prepared by mixing paraffin, asphalt and coal tar according to the weight ratio of 0.5: 0.5: 1, and (2) mixing the components in a ratio.

Example 4:

the invention provides a plastication method of natural rubber, which comprises the following preparation steps:

s1, setting the temperature in the internal mixer to be 150 ℃;

s2, putting 120g of natural rubber into an internal mixer for primary plastication, wherein the plastication time is 7min, then putting 30g of zinc oxide, 8g of vulcanizing agent, 20g of olefin and 7g of softener into the internal mixer for mixing, raising the temperature of the internal mixer to 180 ℃, and keeping the mixing time at 5min, wherein the zinc oxide, the vulcanizing agent, the olefin and the softener are put into the internal mixer in the sequence that the zinc oxide and the softener are put firstly, the interval is 1min, the vulcanizing agent and the olefin are put in, and the natural rubber needs to be cut into blocks of 6cm before being put into an open mixer;

s3, placing the rubber material subjected to primary plastication into an open mill for secondary plastication, wherein the plastication time is 7min, the roller temperature is set at 45 ℃, the roller spacing is set at 0.8mm, and the rubber material subjected to primary plastication is placed into the open mill for cooling for 2 h;

s4, sequentially putting 8g of phenolic resin and 6g of wear-resistant agent into an open mill for plastication, wherein the plastication time is 5min, then adding 15g of anti-aging agent for plastication, the plastication time is 3min, when plastication is carried out, cutting knives are needed to be carried out on refined natural rubber for multiple times so as to be beneficial to heat dissipation and obtain uniform plasticity, and after the natural rubber is subjected to first thin-pass, the natural rubber is added in a twisting mode for 90 degrees for the second time, wherein the adding interval time of the phenolic resin and the wear-resistant agent is 2 min;

and S5, after the second plastication, putting the rubber compound into a calender, so that the calender improves the mixing uniformity of the rubber compound plasticated for the second time, thereby improving the plasticity.

S6, putting the rubber material in the calender into an extruder, setting the body temperature of the calender to 65 ℃, the head temperature to 85 ℃ and the mouth temperature to 95 ℃, so as to achieve the effects of extruding and primarily forming the rubber material;

and S7, vulcanizing the preliminarily molded rubber compound to obtain the product.

Further, the vulcanizing agent is prepared from N' -m-phenylene bismaleimide and sulfur according to the weight ratio of 1: 0.4 proportion.

Furthermore, the material of the wear-resisting agent is polyurethane.

Furthermore, the material of the anti-aging agent is high styrene.

Further, the softening agent is prepared from paraffin, asphalt and coal tar according to the weight ratio of 1: 0.5: 0.5 proportion.

The following data were obtained by comparing the natural rubbers prepared in examples 1 to 4 above:

as can be seen from the above table, the natural rubber prepared in examples 1 to 4 has better performance in terms of wear resistance, elasticity, aging resistance and hardness, but the natural rubber has different effects in terms of wear resistance, elasticity, aging resistance and hardness due to different proportions of the natural rubber, zinc oxide, vulcanizing agent, olefin, anti-aging agent, wear resistance agent, softening agent and phenolic resin, wherein: natural rubber is as the major ingredient, and add the polyurethane of suitable proportion when mixing rubber, great improvement natural rubber's wearability, thereby can improve natural rubber's life, the rethread adds the high styrene of suitable proportion, thereby can improve natural rubber's ageing resistance, and add the phenolic resin of suitable proportion again, natural rubber's hardness has been improved, thereby can let natural rubber soft and medium hardness, improve the suitability, after the use, embodiment 7 effect is best, certain elasticity has been kept when improving hardness, and it has efficient wearability and ageing resistance to go back the bar, thereby application range has been improved.

The above description is only a preferred embodiment of the present invention, and any person skilled in the art may modify the present invention or modify it into an equivalent technical solution by using the technical solution described above. Therefore, any simple modifications or equivalent substitutions made in accordance with the technical solution of the present invention are within the scope of the claims of the present invention.