Toughened regenerated polyethylene plastic and preparation process thereof

Abstract

The invention discloses a toughened regenerated polyethylene plastic and a preparation process thereof, and relates to the technical field of resource regeneration. In order to improve the mechanical property of the regenerated polyethylene plastic, the high-density polyethylene material and the recycled polyethylene material are mixed, so that the defect of poor performance of the recycled polyethylene is overcome; on the basis, a toughening modification auxiliary agent is added into the toughened regenerated polyethylene plastic, a borosilicate modified toughening agent containing siloxane, borane and unsaturated double bonds is prepared by taking decaborane as a raw material, and after the borosilicate modified toughening agent is mixed with an initiator, the toughening modification auxiliary agent is added into the toughened regenerated polyethylene plastic. And the double bonds react with unsaturated double bonds in the recovered polyethylene material under the action of the initiator, so that the molecular weight of the chain segment of the recovered polyethylene resin is increased, siloxane and borane are introduced into the chain segment, the high-temperature resistance and impact resistance of the recovered material are further improved, and the mechanical property of the material is improved.

Description

Technical Field

[0001] The invention relates to the technical field of resource recycling, in particular to a toughened recycled polyethylene plastic and a preparation process thereof. Background Art

[0002] With the development of my country's plastic chemical industry, plastic production has increased year by year, and the amount of plastic waste has also increased every year; waste plastics cannot be naturally decomposed in nature and will have a serious impact on the environment, so the recycling of waste plastics has become of great significance.

[0003] At present, polyethylene plastics account for a considerable proportion of waste plastics, so the recycling and reuse of polyethylene plastics in waste plastics is a hot topic in the field of plastic recycling. Currently, recycled polyethylene materials often experience a decline in performance and cannot fully meet the needs of modern industry. Therefore, it is necessary to study the defects of recycled polyethylene plastics. Summary of the invention

[0004] The purpose of the present invention is to provide a toughened recycled polyethylene plastic and a preparation process thereof to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solution: A toughened recycled polyethylene plastic having the following technical features: the toughened recycled polyethylene plastic is composed of 50-80 parts of recycled polyethylene material, 5.6-10.75 parts of toughening and modifying additives, 15-20 parts of high-density polyethylene material, and 0.5-1.5 parts of masterbatch by weight;

[0006] The toughening and modifying auxiliary agent is composed of 1-1.5 parts of paraffin oil, 3.5-7 parts of borosilicate modified toughening agent, 0.1-0.25 parts of initiator, and 1-2 parts of styrene.

[0007] Furthermore, the initiator is benzoyl peroxide.

[0008] Furthermore, a process for preparing toughened recycled polyethylene plastic comprises the following steps:

[0009] S1. Preparation of borosilicate modified toughening agent;

[0010] S11. Under nitrogen atmosphere, heat toluene to 105-110°C and dry for 5-10 min, then cool to room temperature, add decaborane, mix well, add acetonitrile, heat to 79-82°C, reflux with stirring for 2-4 h, stop heating, cool to 15-25°C, add bis(4-aminophenyl)acetylene, keep stirring for 0.5-1 h, heat to 80-81°C, continue reflux with stirring for 12-24 h, and remove excess solvent by rotary evaporation to obtain an amino-terminated borane intermediate;

[0011] S12. The amino-terminated borane intermediate is dispersed in a toluene solvent, heated to 50-60°C, stirred and mixed for 1-2 hours, trimethylamine is added thereto, and the mixture is continued to be mixed for 5-10 minutes. After cooling to room temperature, the mixture is added dropwise to 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane, and the temperature of the reaction system is continuously stirred and controlled to be 25-30°C during the addition. After the addition is completed, the reaction system is slowly heated to 78-95°C, stirred and reacted for 2-4 hours, and the excess solvent is removed by rotary evaporation. The dried product is washed with deionized water at a temperature of 0-4°C, and dried to constant weight to obtain an epoxy-terminated borosilicate intermediate;

[0012] S13. Under a nitrogen atmosphere, diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0013] Disperse maleic anhydride and trimethylamine in a pure toluene solvent, mix well, and then dropwise add the mixture into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-30°C. After the dropwise addition, heat the mixture to 75-95°C, stir the mixture for reaction for 2-4h, add the epoxy-terminated borosilicate intermediate, continue stirring the mixture for reaction for 4-12h, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0014] S2. Preparation of toughening and modifying additives;

[0015] Paraffin oil and borosilicate modified toughening agent are mixed, and after blending for 2-4 minutes, styrene is added thereto, and after continuing to mix for 1-3 minutes, an initiator is added, and after blending again for 1-2 minutes, a toughening modified auxiliary agent is obtained;

[0016] S3. Preparation of toughened recycled polyethylene plastic;

[0017] The recycled polyethylene material is mixed with the toughening and modifying additive, and after being evenly mixed, the high-density polyethylene material and the masterbatch are added, and after being mixed again for 2-5 minutes, the mixture is melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0018] Furthermore, in step S11, the volume ratio of toluene to acetonitrile is 5:(1-3).

[0019] Furthermore, in step S11, the mass ratio of decaborane to bis(4-aminophenyl)acetylene is 1:(1.4-1.7).

[0020] Furthermore, in step S12, the mass ratio of the terminal amino borane intermediate, trimethylamine, and 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane is 1:(0.01-0.04):(1.6-2.25).

[0021] Furthermore, in step S13, the mass ratio of diphenylmethane diisocyanate, maleic anhydride and trimethylamine is 1:(0.32-0.4):(0.01-0.02).

[0022] Furthermore, in step S13, the mass ratio of the diphenylmethane diisocyanate to the epoxy-terminated borosilicate intermediate is 1:(3-4.2).

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] In order to improve the mechanical properties of recycled polyethylene plastics, the present invention uses a mixture of high-density polyethylene material and recycled polyethylene material, thereby improving the defect of poor performance of recycled polyethylene;

[0025] On this basis, the present invention also adds a toughening modification auxiliary agent to the toughened recycled polyethylene plastic, and uses decaborane as a raw material, reacts it with bis(4-aminophenyl)acetylene containing an acetylene group, and uses the reaction between the acetylene group and the decaborane to graft, thereby preparing an amino-terminated borane intermediate, and the present invention further reacts it with 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane whose terminal group is an epoxy group, and uses the amino group to attack the ring-opening epoxy group, thereby grafting borane and siloxane together. The introduction of borane and siloxane can effectively improve the thermal stability of the recycled polyethylene and improve its flame retardant properties, and the introduction of silicon-oxygen bonds can provide the recycled polyethylene segments with higher segment mobility, improve the flexibility of the resin, and enhance the impact resistance of the material;

[0026] The present invention also uses maleic anhydride to react with diphenylmethane diisocyanate, thereby combining the carbon-carbon unsaturated double bond with the isocyanate group, and further reacting it with the terminal epoxy group of the borosilicate modified toughening agent, thereby introducing unsaturated double bonds in the borosilicate modified toughening agent, and after mixing it with an initiator, the double bonds will react with the unsaturated double bonds in the recovered polyethylene material under the action of the initiator, thereby increasing the molecular weight of the recycled polyethylene resin chain segment while introducing siloxane and borane into the chain segment, further improving the high temperature resistance and impact resistance of the recycled material, and improving the mechanical properties of the material. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The recycled polyethylene material used in this application is recycled high-density polyethylene, the melt index (MFI, 190°C / 5Kg) is 5.9g / 10min, and the high-density polyethylene used is high-density polyethylene 2200J;

[0029] Embodiment 1. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0030] S1. Preparation of borosilicate modified toughening agent;

[0031] S11. Under a nitrogen atmosphere, toluene was heated to 110°C and dried for 10 minutes, then cooled to room temperature, 1 part of decaborane was added thereto, mixed evenly, acetonitrile was added thereto, the temperature was raised to 91°C, refluxed and stirred for 3 hours, heating was stopped, cooled to 20°C, 1.4 parts of bis(4-aminophenyl)acetylene were added thereto, the temperature was kept stirred for 0.5 hours, the temperature was raised to 81°C, refluxed and stirred for 18 hours, and the excess solvent was removed by rotary evaporation to obtain an amino-terminated borane intermediate;

[0032] Wherein, the volume ratio of toluene to acetonitrile is 5:1;

[0033] S12. Disperse 1 part of the terminal amino borane intermediate in toluene solvent by weight, heat to 54°C, stir and mix for 1 hour, add 0.04 parts of trimethylamine, continue mixing for 5 minutes, cool to room temperature, and drop the mixture into 1.6 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane. Stir continuously during the addition and control the temperature of the reaction system to 25-30°C. After the addition is completed, slowly heat the reaction system to 89°C, stir and react for 4 hours, remove excess solvent by rotary evaporation, wash the dried product with deionized water at a temperature of 0-4°C, and dry to constant weight to obtain the terminal epoxy borosilicate intermediate;

[0034] S13. In parts by weight, under a nitrogen atmosphere, 1 part of diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0035] Disperse 0.32 parts of maleic anhydride and 0.01 parts of trimethylamine in a pure toluene solvent, mix well, and then drop them into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-20°C. After the dropwise addition is completed, heat the mixture to 85°C, stir and react for 3 hours, add 3 parts of an epoxy-terminated borosilicate intermediate, continue to stir and react for 12 hours, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0036] S2. Preparation of toughening and modifying additives;

[0037] By weight, 1 part of paraffin oil was mixed with 3.5 parts of borosilicate modified toughening agent, and after blending for 3 minutes, 1 part of styrene was added thereto, and after continuing to mix for 1 minute, 0.1 part of benzoyl peroxide initiator was added, and after blending again for 1 minute, a toughening modification auxiliary agent was obtained;

[0038] S3. Preparation of toughened recycled polyethylene plastic;

[0039] By weight, 65 parts of recycled polyethylene material and 5.6 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0040] Embodiment 2. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0041] Compared with Example 1, the present embodiment increases the amount of bis(4-aminophenyl)acetylene added in step S11;

[0042] S1. Preparation of borosilicate modified toughening agent;

[0043] S11. Under a nitrogen atmosphere, toluene was heated to 110°C and dried for 10 minutes, then cooled to room temperature, 1 part of decaborane was added thereto, mixed evenly, acetonitrile was added thereto, the temperature was raised to 91°C, refluxed and stirred for 3 hours, heating was stopped, the temperature was cooled to 20°C, 1.7 parts of bis(4-aminophenyl)acetylene were added thereto, the temperature was kept stirred for 0.5 hours, the temperature was raised to 81°C, the reflux and stirring reaction was continued for 18 hours, and the excess solvent was removed by rotary evaporation to obtain an amino-terminated borane intermediate;

[0044] Wherein, the volume ratio of toluene to acetonitrile is 5:1;

[0045] S12. Disperse 1 part of the terminal amino borane intermediate in toluene solvent by weight, heat to 54°C, stir and mix for 1 hour, add 0.04 parts of trimethylamine, continue mixing for 5 minutes, cool to room temperature, and drop the mixture into 1.6 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane. Stir continuously during the addition and control the temperature of the reaction system to 25-30°C. After the addition is completed, slowly heat the reaction system to 89°C, stir and react for 4 hours, remove excess solvent by rotary evaporation, wash the dried product with deionized water at a temperature of 0-4°C, and dry to constant weight to obtain the terminal epoxy borosilicate intermediate;

[0046] S13. In parts by weight, under a nitrogen atmosphere, 1 part of diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0047] Disperse 0.32 parts of maleic anhydride and 0.01 parts of trimethylamine in a pure toluene solvent, mix well, and then drop them into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-20°C. After the dropwise addition is completed, heat the mixture to 85°C, stir and react for 3 hours, add 3 parts of an epoxy-terminated borosilicate intermediate, continue to stir and react for 12 hours, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0048] S2. Preparation of toughening and modifying additives;

[0049] By weight, 1 part of paraffin oil was mixed with 3.5 parts of borosilicate modified toughening agent, and after blending for 3 minutes, 1 part of styrene was added thereto, and after continuing to mix for 1 minute, 0.1 part of benzoyl peroxide initiator was added, and after blending again for 1 minute, a toughening modification auxiliary agent was obtained;

[0050] S3. Preparation of toughened recycled polyethylene plastic;

[0051] By weight, 65 parts of recycled polyethylene material and 5.6 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0052] Embodiment 3. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0053] Compared with Example 2, this example increases the amount of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane added in step S12;

[0054] S1. Preparation of borosilicate modified toughening agent;

[0055] S11. Under a nitrogen atmosphere, toluene was heated to 110°C and dried for 10 minutes, then cooled to room temperature, 1 part of decaborane was added thereto, mixed evenly, acetonitrile was added thereto, the temperature was raised to 91°C, refluxed and stirred for 3 hours, heating was stopped, the temperature was cooled to 20°C, 1.7 parts of bis(4-aminophenyl)acetylene were added thereto, the temperature was kept stirred for 0.5 hours, the temperature was raised to 81°C, the reflux and stirring reaction was continued for 18 hours, and the excess solvent was removed by rotary evaporation to obtain an amino-terminated borane intermediate;

[0056] Wherein, the volume ratio of toluene to acetonitrile is 5:1;

[0057] S12. Disperse 1 part of the terminal amino borane intermediate in toluene solvent by weight, heat to 54°C, stir and mix for 1 hour, add 0.04 parts of trimethylamine, continue mixing for 5 minutes, cool to room temperature, and drop the mixture into 2.25 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane. Stir continuously during the addition and control the temperature of the reaction system to 25-30°C. After the addition is completed, slowly heat the reaction system to 89°C, stir and react for 4 hours, remove excess solvent by rotary evaporation, wash the dried product with deionized water at a temperature of 0-4°C, and dry to constant weight to obtain the terminal epoxy borosilicate intermediate;

[0058] S13. In parts by weight, under a nitrogen atmosphere, 1 part of diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0059] Disperse 0.32 parts of maleic anhydride and 0.01 parts of trimethylamine in a pure toluene solvent, mix well, and then drop them into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-20°C. After the dropwise addition is completed, heat the mixture to 85°C, stir and react for 3 hours, add 3 parts of an epoxy-terminated borosilicate intermediate, continue to stir and react for 12 hours, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0060] S2. Preparation of toughening and modifying additives;

[0061] By weight, 1 part of paraffin oil was mixed with 3.5 parts of borosilicate modified toughening agent, and after blending for 3 minutes, 1 part of styrene was added thereto, and after continuing to mix for 1 minute, 0.1 part of benzoyl peroxide initiator was added, and after blending again for 1 minute, a toughening modification auxiliary agent was obtained;

[0062] S3. Preparation of toughened recycled polyethylene plastic;

[0063] By weight, 65 parts of recycled polyethylene material and 5.6 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0064] Embodiment 4. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0065] Compared with Example 3, this embodiment increases the amount of maleic anhydride added in step S13;

[0066] S1. Preparation of borosilicate modified toughening agent;

[0067] S11. Under a nitrogen atmosphere, toluene was heated to 110°C and dried for 10 minutes, then cooled to room temperature, 1 part of decaborane was added thereto, mixed evenly, acetonitrile was added thereto, the temperature was raised to 91°C, refluxed and stirred for 3 hours, heating was stopped, the temperature was cooled to 20°C, 1.7 parts of bis(4-aminophenyl)acetylene were added thereto, the temperature was kept stirred for 0.5 hours, the temperature was raised to 81°C, the reflux and stirring reaction was continued for 18 hours, and the excess solvent was removed by rotary evaporation to obtain an amino-terminated borane intermediate;

[0068] Wherein, the volume ratio of toluene to acetonitrile is 5:1;

[0069] S12. Disperse 1 part of the terminal amino borane intermediate in toluene solvent by weight, heat to 54°C, stir and mix for 1 hour, add 0.04 parts of trimethylamine, continue mixing for 5 minutes, cool to room temperature, and drop the mixture into 2.25 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane. Stir continuously during the addition and control the temperature of the reaction system to 25-30°C. After the addition is completed, slowly heat the reaction system to 89°C, stir and react for 4 hours, remove excess solvent by rotary evaporation, wash the dried product with deionized water at a temperature of 0-4°C, and dry to constant weight to obtain the terminal epoxy borosilicate intermediate;

[0070] S13. In parts by weight, under a nitrogen atmosphere, 1 part of diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0071] Disperse 0.4 parts of maleic anhydride and 0.01 parts of trimethylamine in a pure toluene solvent, mix well, and then dropwise add the mixture into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-20°C. After the dropwise addition is completed, heat the mixture to 85°C, stir the mixture for reaction for 3 hours, add 3 parts of an epoxy-terminated borosilicate intermediate, continue stirring the mixture for reaction for 12 hours, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0072] S2. Preparation of toughening and modifying additives;

[0073] By weight, 1 part of paraffin oil was mixed with 3.5 parts of borosilicate modified toughening agent, and after blending for 3 minutes, 1 part of styrene was added thereto, and after continuing to mix for 1 minute, 0.1 part of benzoyl peroxide initiator was added, and after blending again for 1 minute, a toughening modification auxiliary agent was obtained;

[0074] S3. Preparation of toughened recycled polyethylene plastic;

[0075] By weight, 65 parts of recycled polyethylene material and 5.6 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0076] Embodiment 5. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0077] Compared with Example 4, this embodiment increases the amount of the epoxy-terminated borosilicate intermediate added in step S13;

[0078] S1. Preparation of borosilicate modified toughening agent;

[0079] S11. Under a nitrogen atmosphere, toluene was heated to 110°C and dried for 10 minutes, then cooled to room temperature, 1 part of decaborane was added thereto, mixed evenly, acetonitrile was added thereto, the temperature was raised to 91°C, refluxed and stirred for 3 hours, heating was stopped, the temperature was cooled to 20°C, 1.7 parts of bis(4-aminophenyl)acetylene were added thereto, the temperature was kept stirred for 0.5 hours, the temperature was raised to 81°C, the reflux and stirring reaction was continued for 18 hours, and the excess solvent was removed by rotary evaporation to obtain an amino-terminated borane intermediate;

[0080] Wherein, the volume ratio of toluene to acetonitrile is 5:1;

[0081] S12. Disperse 1 part of the terminal amino borane intermediate in toluene solvent by weight, heat to 54°C, stir and mix for 1 hour, add 0.04 parts of trimethylamine, continue mixing for 5 minutes, cool to room temperature, and drop the mixture into 2.25 parts of 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane. Stir continuously during the addition and control the temperature of the reaction system to 25-30°C. After the addition is completed, slowly heat the reaction system to 89°C, stir and react for 4 hours, remove excess solvent by rotary evaporation, wash the dried product with deionized water at a temperature of 0-4°C, and dry to constant weight to obtain the terminal epoxy borosilicate intermediate;

[0082] S13. In parts by weight, under a nitrogen atmosphere, 1 part of diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use;

[0083] Disperse 0.4 parts of maleic anhydride and 0.01 parts of trimethylamine in a pure toluene solvent, mix well, and then dropwise add the mixture into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-20°C. After the dropwise addition is completed, heat the mixture to 85°C, stir the mixture for reaction for 3 hours, add 3 parts of an epoxy-terminated borosilicate intermediate, continue stirring the mixture for reaction for 12 hours, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent.

[0084] S2. Preparation of toughening and modifying additives;

[0085] By weight, 1 part of paraffin oil was mixed with 3.5 parts of borosilicate modified toughening agent, and after blending for 3 minutes, 1 part of styrene was added thereto, and after continuing to mix for 1 minute, 0.1 part of benzoyl peroxide initiator was added, and after blending again for 1 minute, a toughening modification auxiliary agent was obtained;

[0086] S3. Preparation of toughened recycled polyethylene plastic;

[0087] By weight, 65 parts of recycled polyethylene material and 5.6 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0088] Embodiment 6. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0089] Compared with Example 5, this example increases the amount of toughening and modifying additive added in step S3;

[0090] S2. Preparation of toughening and modifying additives;

[0091] By weight, 1.5 parts of paraffin oil and 7 parts of borosilicate modified toughening agent were mixed, and after blending for 3 minutes, 2 parts of styrene were added thereto, and after continuing to mix for 1 minute, 0.25 parts of benzoyl peroxide initiator were added, and after blending again for 1 minute, a toughening modified auxiliary agent was obtained;

[0092] S3. Preparation of toughened recycled polyethylene plastic;

[0093] By weight, 65 parts of recycled polyethylene material and 10.75 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0094] Comparative Example 1. A process for preparing toughened recycled polyethylene plastic, comprising the following steps:

[0095] Compared with Example 1, this comparative example did not prepare the addition of borosilicate modified toughening agent;

[0096] S1. Preparation of toughening and modifying additives;

[0097] By weight, 1 part of paraffin oil and 1 part of styrene were mixed for 1 minute, and then 0.1 part of benzoyl peroxide initiator was added, and the mixture was blended again for 1 minute to obtain a toughening and modification additive;

[0098] S2. Preparation of toughened recycled polyethylene plastic;

[0099] By weight, 65 parts of recycled polyethylene material and 2.1 parts of toughening and modifying additives were mixed and stirred. After mixing evenly, 15 parts of high-density polyethylene material and 0.5 parts of masterbatch were added. After mixing again for 2 minutes, the mixture was melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

[0100] Testing: The toughened recycled polyethylene plastics prepared in Examples 1-6 and Comparative Example 1 were injection molded into test samples;

[0101] According to GB / T 1043.1-2008, the samples prepared in Examples 1-6 and Comparative Example 1 were tested for impact strength;

[0102] According to GB / T 1040-2006, the tensile strength of the samples prepared in Examples 1-6 and Comparative Example 1 was tested at a tensile rate of 50 mm / min and a gauge length of 25 mm;

[0103] According to GB / T 2406.2-2009, the samples prepared in Examples 1-6 and Comparative Example 1 were tested for limiting oxygen index. The test results are shown in the following table;

[0104]

[0105] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A toughened recycled polyethylene plastic, characterized in that: The toughened recycled polyethylene plastic is composed of 50-80 parts of recycled polyethylene material, 5.6-10.75 parts of toughening and modifying additives, 15-20 parts of high-density polyethylene material, and 0.5-1.5 parts of masterbatch by weight; The toughening and modifying auxiliary agent is composed of 1-1.5 parts of paraffin oil, 3.5-7 parts of borosilicate modified toughening agent, 0.1-0.25 parts of initiator, and 1-2 parts of styrene.

2. The toughened recycled polyethylene plastic according to claim 1, characterized in that: The initiator is benzoyl peroxide.

3. A process for preparing toughened recycled polyethylene plastic according to any one of claims 1 to 2, characterized in that: The following steps are involved: S1. Preparation of borosilicate modified toughening agent; S11. Under nitrogen atmosphere, heat toluene to 105-110°C and dry for 5-10 min, then cool to room temperature, add decaborane, mix well, add acetonitrile, heat to 79-82°C, reflux with stirring for 2-4 h, stop heating, cool to 15-25°C, add bis(4-aminophenyl)acetylene, keep stirring for 0.5-1 h, heat to 80-81°C, continue reflux with stirring for 12-24 h, and remove excess solvent by rotary evaporation to obtain an amino-terminated borane intermediate; S12. The amino-terminated borane intermediate is dispersed in a toluene solvent, heated to 50-60°C, stirred and mixed for 1-2 hours, trimethylamine is added thereto, and the mixture is continued to be mixed for 5-10 minutes. After cooling to room temperature, the mixture is added dropwise to 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane, and the temperature of the reaction system is continuously stirred and controlled to be 25-30°C during the addition. After the addition is completed, the reaction system is slowly heated to 78-95°C, stirred and reacted for 2-4 hours, and the excess solvent is removed by rotary evaporation. The dried product is washed with deionized water at a temperature of 0-4°C, and dried to constant weight to obtain an epoxy-terminated borosilicate intermediate; S13. Under a nitrogen atmosphere, diphenylmethane diisocyanate was dispersed in toluene, stirred and mixed evenly, and allowed to stand for use; Disperse maleic anhydride and trimethylamine in a pure toluene solvent, mix well, and then dropwise add the mixture into a toluene solution containing diphenylmethane diisocyanate. During the dropwise addition, control the temperature of the reaction system to be 15-30°C. After the dropwise addition, heat the mixture to 75-95°C, stir the mixture for reaction for 2-4h, add the epoxy-terminated borosilicate intermediate, continue stirring the mixture for reaction for 4-12h, and then remove excess solvent by rotary evaporation to obtain a borosilicate modified toughening agent. S2. Preparation of toughening and modifying additives; Paraffin oil and borosilicate modified toughening agent are mixed, and after blending for 2-4 minutes, styrene is added thereto, and after continuing to mix for 1-3 minutes, an initiator is added, and after blending again for 1-2 minutes, a toughening modified auxiliary agent is obtained; S3. Preparation of toughened recycled polyethylene plastic; The recycled polyethylene material is mixed with the toughening and modifying additive, and after being evenly mixed, the high-density polyethylene material and the masterbatch are added, and after being mixed again for 2-5 minutes, the mixture is melted, extruded and pelletized to obtain toughened recycled polyethylene plastic.

4. The process for preparing toughened recycled polyethylene plastic according to claim 3, characterized in that: In step S11, the volume ratio of toluene to acetonitrile is 5:(1-3).

5. The process for preparing toughened recycled polyethylene plastic according to claim 3, characterized in that: In step S11, the mass ratio of decaborane to bis(4-aminophenyl)acetylene is 1:(1.4-1.7).

6. The process for preparing toughened recycled polyethylene plastic according to claim 3, characterized in that: In step S12, the mass ratio of the terminal amino borane intermediate, trimethylamine, and 1,1,3,3-tetramethyl-1,3-bis[3-(oxiranylmethoxy)propyl]disiloxane is 1:(0.01-0.04):(1.6-2.25).

7. The process for preparing toughened recycled polyethylene plastic according to claim 3, characterized in that: In step S13, the mass ratio of diphenylmethane diisocyanate, maleic anhydride and trimethylamine is 1:(0.32-0.4):(0.01-0.02).

8. The process for preparing toughened recycled polyethylene plastic according to claim 3, characterized in that: In step S13, the mass ratio of the diphenylmethane diisocyanate to the epoxy-terminated borosilicate intermediate is 1:(3-4.2).

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