CN114213834A - TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof - Google Patents

TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof Download PDF

Info

Publication number
CN114213834A
CN114213834A CN202111654588.9A CN202111654588A CN114213834A CN 114213834 A CN114213834 A CN 114213834A CN 202111654588 A CN202111654588 A CN 202111654588A CN 114213834 A CN114213834 A CN 114213834A
Authority
CN
China
Prior art keywords
mobile phone
reaction
stirring
phone protective
injection molding
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
CN202111654588.9A
Other languages
Chinese (zh)
Inventor
吴跃进
谢春平
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Dalanying Communication Technology Co ltd
Original Assignee
Shenzhen Dalanying Communication Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Dalanying Communication Technology Co ltd filed Critical Shenzhen Dalanying Communication Technology Co ltd
Priority to CN202111654588.9A priority Critical patent/CN114213834A/en
Publication of CN114213834A publication Critical patent/CN114213834A/en
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/49—Phosphorus-containing compounds
    • C08K5/50—Phosphorus bound to carbon only
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02—Phosphorus compounds
    • C07F9/547—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom
    • C07F9/645—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having two nitrogen atoms as the only ring hetero atoms
    • C07F9/6503—Five-membered rings
    • C07F9/6506—Five-membered rings having the nitrogen atoms in positions 1 and 3
    • C07F9/65068—Five-membered rings having the nitrogen atoms in positions 1 and 3 condensed with carbocyclic rings or carbocyclic ring systems
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/28—Nitrogen-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C08K3/36—Silica
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/38—Boron-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2217—Oxides; Hydroxides of metals of magnesium
    • C08K2003/222—Magnesia, i.e. magnesium oxide
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2227—Oxides; Hydroxides of metals of aluminium
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/28—Nitrogen-containing compounds
    • C08K2003/282—Binary compounds of nitrogen with aluminium
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/38—Boron-containing compounds
    • C08K2003/382—Boron-containing compounds and nitrogen
    • C08K2003/385—Binary compounds of nitrogen with boron

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

The invention discloses TPU (thermoplastic polyurethane) plastic for injection molding of a mobile phone protective sleeve and a production process thereof, and relates to the field of plastics, wherein a thermoplastic polyurethane elastomer, a heat-conducting filler, a coupling agent, an antibacterial agent and an antioxidant are uniformly mixed to obtain a mixture, the mixture is added into an extruder to be melted and extruded and granulated to obtain the TPU plastic for injection molding of the mobile phone protective sleeve, the TPU plastic is melted and extruded into a mould of the mobile phone protective sleeve to form the mobile phone protective sleeve, the prepared mobile phone protective sleeve has good elasticity and can effectively protect a mobile phone, heat emitted by the mobile phone can be rapidly discharged by adding the heat-conducting filler, the heat radiation of the mobile phone is prevented from being limited by using the mobile phone protective sleeve, so that the performance of the mobile phone is reduced, the mobile phone protective sleeve can be endowed with good antibacterial performance by adding the antibacterial agent, and the breeding of bacteria caused by long-term use of the mobile phone protective sleeve is avoided, and then contact with the human body causes the user to get ill.

Description

TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof
Technical Field
The invention relates to the field of plastics, in particular to TPU (thermoplastic polyurethane) plastic for injection molding of a mobile phone protective sleeve and a production process thereof.
Background
The mobile phone protective sleeve is a jacket designed and produced for protecting a mobile phone. In the middle and late twentieth nineties, mobile phone covers are becoming popular with the opportunity of slimming mobile phones. The mobile phone cover is no longer of simple use value, and beauty treatment of the mobile phone becomes a way for showing individuality for young people.
The polyurethane has the advantages of high strength, wear resistance, cold resistance, air permeability, aging resistance, solvent resistance, soft texture and good processability, and is suitable for manufacturing mobile phone protective sleeves.
Investigation shows that 12 ten thousand bacteria are located in each square centimeter of the mobile phone, and according to the calculation, at least millions of bacteria exist in the whole mobile phone, and the peristaltic bacteria are inevitable not to be wiped on the face and other parts when a call is made, so that pimples, pneumonia and meningitis can be caused, and skin pimples are greatly related to the mobile phone which is frequently used and polluted by germs. Moreover, the diseases brought by the mobile phone are not limited to the category of skin diseases. Many mobile phone users have the habit of calling while eating things, and bacteria on the mobile phone enter human bodies. Therefore, the mobile phone bacteria just influence the health of people silently, and the use of the mobile phone protective sleeve limits the heat dissipation of the mobile phone, so that the performance of the mobile phone is reduced.
How to improve the antibacterial property and the heat conductivity of the conventional mobile phone protective case is the key of the invention, so that a TPU plastic for injection molding of the mobile phone protective case and a production process thereof are urgently needed to solve the problems.
Disclosure of Invention
In order to overcome the technical problems, the invention aims to provide TPU plastic for injection molding of a mobile phone protective sleeve and a production process thereof, wherein the TPU plastic comprises the following steps: the thermoplastic polyurethane elastomer, the heat-conducting filler, the coupling agent, the antibacterial agent and the antioxidant are uniformly mixed to obtain a mixed material, the mixed material is added into an extruder to be melted and extruded, and granulation is carried out to obtain the TPU plastic for injection molding of the mobile phone protective sleeve, so that the problems of poor antibacterial performance and poor heat-conducting performance of the conventional mobile phone protective sleeve are solved.
The purpose of the invention can be realized by the following technical scheme:
the TPU plastic for injection molding of the mobile phone protective sleeve comprises the following components in parts by weight:
50-70 parts of thermoplastic polyurethane elastomer, 4-9 parts of heat-conducting filler, 0.5-1.5 parts of coupling agent, 2-8 parts of antibacterial agent and 0.2-1.0 part of antioxidant;
the antibacterial agent is prepared by the following steps:
the method comprises the following steps: adding acetic anhydride and glacial acetic acid into a three-neck flask provided with a stirrer, a thermometer and a constant-pressure dropping funnel, dropwise adding para-fluoroaniline solution while stirring under the conditions that the temperature is-3-0 ℃ and the stirring rate is 300-500r/min, controlling the dropwise adding rate to be 1-2 drops/s, continuously stirring and reacting for 30-50min after the dropwise adding is finished, dropwise adding mixed acid while stirring, controlling the dropwise adding rate to be 1-2 drops/s, continuously stirring and reacting for 1-2h after the dropwise adding is finished, pouring a reaction product into ice water after the reaction is finished, precipitating and filtering, adding a filter cake into a vacuum drying box, and drying to constant weight under the condition that the temperature is 50-70 ℃ to obtain an intermediate 1;
the reaction principle is as follows:
Figure BDA0003447926870000021
step two: adding the intermediate 1 and a hydrochloric acid solution into a three-neck flask provided with a stirrer, a thermometer and a reflux condenser, stirring and heating to reflux under the condition that the stirring speed is 200-300r/min, then stirring at constant temperature for reaction for 1-2h, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, performing suction filtration, washing a filter cake to be neutral by using a saturated sodium carbonate solution, then washing by using distilled water for 2-3 times, then placing in a vacuum drying box, and drying to constant weight under the condition that the temperature is 50-70 ℃ to obtain an intermediate 2;
the reaction principle is as follows:
Figure BDA0003447926870000031
step three: adding the intermediate 2, absolute ethyl alcohol and 8% palladium carbon into a reaction kettle, introducing nitrogen for protection, then introducing hydrogen for replacing nitrogen, controlling the pressure to be 0.9-1.1MPa, continuously introducing hydrogen while stirring under the conditions that the temperature is 25-30 ℃ and the stirring speed is 500r/min, continuously stirring for reaction for 8-10h, filtering a reaction product after the reaction is finished, and carrying out rotary evaporation and drying on filtrate to obtain an intermediate 3;
the reaction principle is as follows:
Figure BDA0003447926870000032
step four: adding the intermediate 3 and dichloromethane into a three-neck flask provided with a stirrer, a thermometer and a constant pressure dropping funnel, stirring at the temperature of 20-30 ℃ and the stirring rate of 300-500r/min until the intermediate 3 is completely dissolved, then adding triethylamine, continuously stirring for 5-10min, then dropwise adding phosgene solution while stirring, controlling the dropwise adding rate to be 1-2 drops/s, continuously stirring and reacting for 20-30h after the dropwise adding is finished, adding a reaction product into distilled water after the reaction is finished, continuously stirring for 3-5min, precipitating, carrying out suction filtration, placing a filter cake into a vacuum drying box, drying at the temperature of 50-70 ℃ to constant weight, and obtaining an intermediate 4;
the reaction principle is as follows:
Figure BDA0003447926870000041
step five: adding terephthalyl alcohol and acetic anhydride into a four-neck flask provided with a stirrer, a thermometer, a reflux condenser tube and a constant-pressure dropping funnel, then stirring and dropwise adding hydrobromic acid under the conditions that the temperature is 20-30 ℃ and the stirring rate is 300-500r/min, controlling the dropwise adding rate to be 1-2 drops/s, heating to reflux after the dropwise adding is finished, continuing stirring for reaction for 10-12h, adjusting the pH of a reaction product to be 7.5-8.0 by using a saturated sodium carbonate solution after the reaction is finished, separating out a solid, performing suction filtration, placing a filter cake into a vacuum drying box, and drying to constant weight under the condition that the temperature is 50-70 ℃ to obtain an intermediate 5;
the reaction principle is as follows:
Figure BDA0003447926870000042
step six: adding the intermediate 4 and N, N-dimethylformamide into a three-neck flask provided with a stirrer and a thermometer, then stirring for 10-20min under the conditions that the temperature is 20-30 ℃ and the stirring rate is 500r/min, then adding potassium carbonate, continuously stirring for 5-10min, then adding the intermediate 5, then stirring at constant temperature for reaction for 15-20h, adding deionized water into a reaction product after the reaction is finished, continuously stirring for 5-10min, then extracting with ethyl acetate, standing for liquid separation, drying an organic phase with anhydrous sodium sulfate, and then rotating to evaporate to dryness to obtain an intermediate 6;
the reaction principle is as follows:
Figure BDA0003447926870000051
step seven: adding sodium, toluene and isoamyl alcohol into a four-neck flask provided with a stirrer, a thermometer, a gas-guide tube and a constant-pressure dropping funnel, introducing nitrogen for protection, melting the sodium at the temperature of 90-100 ℃ and the stirring rate of 800-, carrying out rotary evaporation on the filtrate to remove toluene, and then recrystallizing an evaporation product by using absolute ethyl alcohol to obtain an intermediate 7;
the reaction principle is as follows:
Figure BDA0003447926870000052
step eight: adding the intermediate 6, the intermediate 7, hydroquinone and anhydrous acetonitrile into a three-neck flask provided with a stirrer and a thermometer, stirring and reacting for 60-70h under the conditions that the temperature is 80-90 ℃ and the stirring rate is 500-800r/min, rotating and evaporating a reaction product to dryness after the reaction is finished, and then recrystallizing by using anhydrous ethanol to obtain the antibacterial agent.
The reaction principle is as follows:
Figure BDA0003447926870000061
as a further scheme of the invention: the dosage ratio of the acetic anhydride, the glacial acetic acid, the para-fluoroaniline solution and the mixed acid in the step one is 60 mL: 20mL of: 30g of: 10-15mL, wherein the para-fluoroaniline solution is a mixture of para-fluoroaniline and glacial acetic acid in a mass ratio of 1:1, and the mixed acid is a mixture of nitric acid and sulfuric acid in a volume ratio of 9-11: 1, the mass fraction of the nitric acid is 65-68%, and the mass fraction of the sulfuric acid is 95-98%.
As a further scheme of the invention: the dosage ratio of the intermediate 1 to the hydrochloric acid solution in the second step is 0.01 mol: 120-150mL, and the molar concentration of the hydrochloric acid solution is 9 mol/L.
As a further scheme of the invention: the dosage ratio of the intermediate 2, the palladium carbon with the concentration of 8 percent and the absolute ethyl alcohol in the third step is 0.1 mol: 1.0-1.5 g: 100-.
As a further scheme of the invention: the dosage ratio of the intermediate 3, the dichloromethane, the triethylamine and the phosgene solution in the step four is 0.01 mol: 100mL of: 1.05-1.1 g: 30-40mL, the phosgene solution being phosgene in a ratio of 0.3 g: 10mL of a solution obtained by dissolving methylene chloride in water.
As a further scheme of the invention: the dosage ratio of the terephthalyl alcohol, the acetic anhydride and the hydrobromic acid in the step five is 5.0 g: 80-90 mL: 25mL, and the mass fraction of the hydrobromic acid is 40%.
As a further scheme of the invention: the dosage ratio of the intermediate 4, the N, N-dimethylformamide, the potassium carbonate, the intermediate 5 and the deionized water in the sixth step is 0.02 mol: 150mL of: 10 g: 0.07 mol: 100 mL.
As a further scheme of the invention: and the dosage ratio of the sodium, the toluene, the isoamyl alcohol, the chlorobenzene and the phosphorus trichloride in the step seven is 0.25 mol: 100mL of: 1mL of: 20 g: 0.05 mol.
As a further scheme of the invention: the dosage ratio of the intermediate 6, the intermediate 7, the hydroquinone and the anhydrous acetonitrile in the step eight is 0.1 mol: 0.22 mol: 0.3-0.5 g: 100-.
As a further scheme of the invention: a production process of TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeves comprises the following steps:
the method comprises the following steps: weighing 50-70 parts of thermoplastic polyurethane elastomer, 4-9 parts of heat-conducting filler, 0.5-1.5 parts of coupling agent, 2-8 parts of antibacterial agent and 0.2-1.0 part of antioxidant according to parts by weight for later use;
step two: uniformly mixing a thermoplastic polyurethane elastomer, a heat-conducting filler, a coupling agent, an antibacterial agent and an antioxidant to obtain a mixture;
step three: and adding the mixture into an extruder for melt extrusion, and granulating to obtain the TPU plastic for the injection molding of the mobile phone protective sleeve.
As a further scheme of the invention: the heat-conducting filler is one or a mixture of more than two of magnesium oxide, aluminum oxide, silicon dioxide, boron nitride, aluminum nitride and silicon carbide in any proportion; the coupling agent is one of a silane coupling agent KH-550, a silane coupling agent KH-560 and a silane coupling agent KH-570; the antioxidant is one of antioxidant 168, antioxidant 1010 and antioxidant 1076
The invention has the beneficial effects that:
the invention relates to a TPU plastic for injection molding of a mobile phone protective sleeve and a production process thereof, wherein a thermoplastic polyurethane elastomer, a heat-conducting filler, a coupling agent, an antibacterial agent and an antioxidant are uniformly mixed to obtain a mixture, the mixture is added into an extruder to be melted and extruded and granulated to obtain the TPU plastic for injection molding of the mobile phone protective sleeve, the TPU plastic is melted and extruded into a mould of the mobile phone protective sleeve to form the mobile phone protective sleeve, the prepared mobile phone protective sleeve has good elasticity and can effectively protect a mobile phone, the heat emitted by the mobile phone can be quickly discharged by adding the heat conducting filler, the situation that the heat radiation of the mobile phone is limited by the use of a mobile phone protective sleeve is avoided, therefore, the performance of the mobile phone is reduced, the mobile phone protective sleeve can be endowed with good antibacterial performance by adding the antibacterial agent, and the situation that the mobile phone protective sleeve is used for a long time to breed bacteria and then is contacted with a human body to cause a user to get ill is avoided.
In the process of preparing the TPU plastic for injection molding of the mobile phone protective sleeve, firstly, an antibacterial agent is prepared, after the reaction of para-fluoroaniline and acetic anhydride, nitration is carried out to form an intermediate 1, then the intermediate 1 reacts with hydrochloric acid to generate an intermediate 2, then nitro is reduced into amino by hydrogen to obtain an intermediate 3, then the intermediate 3 reacts with phosgene to generate an intermediate 4, terephthalyl alcohol reacts with hydrobromic acid to generate an intermediate 5, then the intermediate 4 reacts with the intermediate 5 to generate an intermediate 6, chlorobenzene reacts with phosphorus trichloride to generate an intermediate 7, then the intermediate 6 reacts with the intermediate 7 to obtain the antibacterial agent containing a large number of quaternary phosphonium salt groups, the quaternary phosphonium salt groups are positively charged and can be adsorbed to the surface of bacteria, penetrate through cell walls, combine with cell membranes and disturb the composition of the cell membranes to cause the leakage of intracellular substances, finally, bacteria die, so that the antibacterial agent has a good antibacterial and bactericidal effect, and the prepared mobile phone protective case has a good antibacterial effect when added into TPU plastic for injection molding of the mobile phone protective case.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
this embodiment is a method for preparing an antimicrobial agent, comprising the steps of:
the method comprises the following steps: adding 60mL of acetic anhydride and 20mL of glacial acetic acid into a three-neck flask provided with a stirrer, a thermometer and a constant-pressure dropping funnel, dropwise adding 30g of para-fluoroaniline solution formed by mixing para-fluoroaniline and glacial acetic acid according to a mass ratio of 1:1 while stirring at a temperature of-3 ℃ and a stirring speed of 300r/min, controlling the dropwise adding speed to be 1 drop/s, continuously stirring and reacting for 30min after the dropwise adding is finished, and then dropwise adding 65% by mass of nitric acid and 95% by mass of sulfuric acid while stirring according to a volume ratio of 9: 1, controlling the dropping rate to be 1 drop/s, continuing stirring for reacting for 1 hour after the dropping is finished, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, performing suction filtration, adding a filter cake into a vacuum drying oven, and drying at the temperature of 50 ℃ to constant weight to obtain an intermediate 1;
step two: adding 0.01mol of intermediate 1 and 120mL of hydrochloric acid solution with the molar concentration of 9mol/L into a three-neck flask provided with a stirrer, a thermometer and a reflux condenser tube, stirring and heating to reflux at the stirring speed of 200r/min, then stirring at constant temperature for reaction for 1h, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, carrying out suction filtration, washing a filter cake to be neutral by using a saturated sodium carbonate solution, washing for 2 times by using distilled water, then placing in a vacuum drying oven, and drying at the temperature of 50 ℃ to constant weight to obtain an intermediate 2;
step three: adding 0.1mol of intermediate 2, 100mL of absolute ethyl alcohol and 1.0g of 8% palladium carbon into a reaction kettle, introducing nitrogen for protection, then introducing hydrogen for replacing nitrogen, controlling the pressure to be 0.9MPa, continuously introducing hydrogen while stirring at the temperature of 25 ℃ and the stirring speed of 300r/min, continuously stirring for reaction for 8 hours, filtering a reaction product after the reaction is finished, and evaporating filtrate in a rotary manner to dryness to obtain an intermediate 3;
step four: adding 0.01mol of intermediate 3 and 100mL of dichloromethane into a three-neck flask provided with a stirrer, a thermometer and a constant pressure dropping funnel, stirring at the temperature of 20 ℃ and the stirring speed of 300r/min until the intermediate 3 is completely dissolved, then adding 1.05g of triethylamine, continuing stirring for 5min, and then dropwise adding phosgene while stirring according to the proportion of 0.3 g: 10mL of phosgene solution formed by dissolving in dichloromethane is 30mL, the dropping speed is controlled to be 1 drop/s, the stirring and the reaction are continued for 20 hours after the dropping is finished, the reaction product is added into distilled water and is continuously stirred for 3 minutes after the reaction is finished, precipitate is separated out and is filtered, the filter cake is placed in a vacuum drying oven and is dried to constant weight under the condition that the temperature is 50 ℃, and an intermediate 4 is obtained;
step five: adding 5.0g of terephthalyl alcohol and 80mL of acetic anhydride into a four-neck flask provided with a stirrer, a thermometer, a reflux condenser tube and a constant-pressure dropping funnel, then dropwise adding 25mL of hydrobromic acid with the mass fraction of 40% while stirring at the stirring speed of 300r/min at the temperature of 20 ℃, controlling the dropwise adding speed to be 1 drop/s, heating to reflux after the dropwise adding is finished, continuously stirring for reaction for 10 hours, adjusting the pH of a reaction product to be 7.5 by using a saturated sodium carbonate solution after the reaction is finished, separating out a solid, performing suction filtration, placing a filter cake into a vacuum drying box, drying to constant weight at the temperature of 50 ℃ to obtain an intermediate 5;
step six: adding 0.02mol of the intermediate 4 and 150mLN, N-dimethylformamide into a three-neck flask provided with a stirrer and a thermometer, stirring at 20 ℃ and 300r/min for 10min, adding 10g of potassium carbonate, continuously stirring for 5min, adding 0.07mol of the intermediate 5, stirring at constant temperature for reaction for 15h, adding 100mL of deionized water into a reaction product after the reaction is finished, continuously stirring for 5min, extracting with ethyl acetate, standing for liquid separation, drying an organic phase with anhydrous sodium sulfate, and then rotating to evaporate to dryness to obtain an intermediate 6;
step seven: adding 0.25mol of sodium, 100mL of toluene and 1mL of isoamyl alcohol into a four-neck flask provided with a stirrer, a thermometer, a gas-guide tube and a constant-pressure dropping funnel, introducing nitrogen for protection, melting the sodium under the conditions that the temperature is 90 ℃ and the stirring speed is 800r/min, stirring and dispersing, then cooling to 50 ℃ to form sodium sand, then dropwise adding 20g of chlorobenzene while stirring, controlling the dropwise adding speed to be 1 drop/s, heating to 55 ℃ after the dropwise adding, stirring at constant temperature for reaction for 1h, then cooling to 30 ℃ while stirring, dropwise adding 0.05mol of phosphorus trichloride while stirring, controlling the dropwise adding speed to be 1 drop/s, heating to 55 ℃ after the dropwise adding, stirring and reacting for 1h at constant temperature, filtering a reaction product while the reaction product is hot after the reaction is finished, rotationally evaporating the filtrate to remove toluene, and then recrystallizing the evaporation product by absolute ethyl alcohol, to obtain an intermediate 7;
step eight: adding 0.1mol of the intermediate 6, 0.22mol of the intermediate 7, 0.3g of hydroquinone and 100mL of anhydrous acetonitrile into a three-neck flask provided with a stirrer and a thermometer, stirring and reacting for 60 hours at the temperature of 80 ℃ and the stirring rate of 500r/min, evaporating the reaction product to dryness by rotation after the reaction is finished, and then recrystallizing with anhydrous ethanol to obtain the antibacterial agent.
Example 2:
this embodiment is a method for preparing an antimicrobial agent, comprising the steps of:
the method comprises the following steps: adding 60mL of acetic anhydride and 20mL of glacial acetic acid into a three-neck flask provided with a stirrer, a thermometer and a constant-pressure dropping funnel, dropwise adding 30g of para-fluoroaniline solution formed by mixing para-fluoroaniline and glacial acetic acid according to a mass ratio of 1:1 while stirring at the temperature of 0 ℃ and the stirring rate of 500r/min, controlling the dropwise adding rate to be 2 drops/s, continuously stirring and reacting for 50min after the dropwise adding is finished, and then dropwise adding 68% by mass of nitric acid and 98% by mass of sulfuric acid while stirring according to a volume ratio of 11: 1, controlling the dropping rate to be 2 drops/s, continuing stirring for reacting for 2 hours after the dropping is finished, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, performing suction filtration, adding a filter cake into a vacuum drying oven, and drying at the temperature of 70 ℃ to constant weight to obtain an intermediate 1;
step two: adding 0.01mol of intermediate 1 and 150mL of hydrochloric acid solution with the molar concentration of 9mol/L into a three-neck flask provided with a stirrer, a thermometer and a reflux condenser tube, stirring and heating to reflux under the condition that the stirring speed is 300r/min, then stirring at constant temperature for reaction for 2 hours, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, carrying out suction filtration, washing a filter cake to be neutral by using a saturated sodium carbonate solution, then washing for 3 times by using distilled water, then placing in a vacuum drying oven, and drying to constant weight under the condition that the temperature is 70 ℃ to obtain an intermediate 2;
step three: adding 0.1mol of intermediate 2, 150mL of absolute ethyl alcohol and 1.5g of 8% palladium carbon into a reaction kettle, introducing nitrogen for protection, then introducing hydrogen for replacing nitrogen, controlling the pressure to be 1.1MPa, continuously introducing hydrogen while stirring at the temperature of 30 ℃ and the stirring speed of 500r/min, continuously stirring for reaction for 10 hours, filtering a reaction product after the reaction is finished, and evaporating filtrate in a rotary manner to dryness to obtain an intermediate 3;
step four: adding 0.01mol of intermediate 3 and 100mL of dichloromethane into a three-neck flask provided with a stirrer, a thermometer and a constant pressure dropping funnel, stirring at the temperature of 30 ℃ and the stirring speed of 500r/min until the intermediate 3 is completely dissolved, then adding 1.1g of triethylamine, continuing stirring for 10min, and then dropwise adding phosgene while stirring according to the proportion of 0.3 g: 10mL of phosgene solution formed by dissolving in dichloromethane is 40mL, the dropping speed is controlled to be 2 drops/s, stirring and reacting are continuously carried out for 30 hours after the dropping is finished, the reaction product is added into distilled water and stirred continuously for 5 minutes after the reaction is finished, precipitate is separated out and is filtered, a filter cake is placed in a vacuum drying box and is dried to constant weight under the condition that the temperature is 70 ℃, and an intermediate 4 is obtained;
step five: adding 5.0g of terephthalyl alcohol and 90mL of acetic anhydride into a four-neck flask provided with a stirrer, a thermometer, a reflux condenser tube and a constant-pressure dropping funnel, then dropwise adding 25mL of hydrobromic acid with the mass fraction of 40% while stirring at the stirring speed of 500r/min at the temperature of 30 ℃, controlling the dropwise adding speed to be 1-2 drops/s, heating to reflux after the dropwise adding is finished, continuously stirring for reaction for 12 hours, adjusting the pH of a reaction product to be 8.0 by using a saturated sodium carbonate solution after the reaction is finished, separating out a solid, carrying out suction filtration, placing a filter cake into a vacuum drying oven, drying to constant weight at the temperature of 70 ℃ to obtain an intermediate 5;
step six: adding 0.02mol of the intermediate 4 and 150mLN, N-dimethylformamide into a three-neck flask provided with a stirrer and a thermometer, stirring for 20min under the conditions that the temperature is 30 ℃ and the stirring rate is 500r/min, then adding 10g of potassium carbonate, continuously stirring for 10min, then adding 0.07mol of the intermediate 5, stirring at constant temperature for reaction for 20h, adding 100mL of deionized water into a reaction product after the reaction is finished, continuously stirring for 10min, then extracting with ethyl acetate, standing for liquid separation, drying an organic phase with anhydrous sodium sulfate, and then rotating to evaporate to dryness to obtain an intermediate 6;
step seven: adding 0.25mol of sodium, 100mL of toluene and 1mL of isoamyl alcohol into a four-neck flask provided with a stirrer, a thermometer, a gas-guide tube and a constant-pressure dropping funnel, introducing nitrogen for protection, melting the sodium at 100 ℃ and at a stirring speed of 1000r/min, stirring and dispersing, cooling to 55 ℃ to form sodium sand, dropwise adding 20g of chlorobenzene while stirring, controlling the dropwise adding speed to be 2 drops/s, heating to 60 ℃ after dropwise adding, stirring at constant temperature for reaction for 1.5 hours, cooling to 35 ℃ while stirring, dropwise adding 0.05mol of phosphorus trichloride while stirring, controlling the dropwise adding speed to be 2 drops/s, heating to 60 ℃ after dropwise adding, stirring at constant temperature for reaction for 1.5 hours, filtering a reaction product while the reaction product is hot after the reaction is finished, rotationally evaporating a filtrate to remove toluene, recrystallizing an evaporation product by using absolute ethyl alcohol, to obtain an intermediate 7;
step eight: adding 0.1mol of the intermediate 6, 0.22mol of the intermediate 7, 0.5g of hydroquinone and 150mL of anhydrous acetonitrile into a three-neck flask provided with a stirrer and a thermometer, stirring and reacting for 70 hours at the temperature of 90 ℃ and the stirring rate of 800r/min, evaporating the reaction product to dryness in a rotating manner after the reaction is finished, and then recrystallizing with anhydrous ethanol to obtain the antibacterial agent.
Example 3:
the embodiment is a production process of TPU plastic for injection molding of a mobile phone protective sleeve, which comprises the following steps:
the method comprises the following steps: weighing 50 parts of thermoplastic polyurethane elastomer, 4 parts of aluminum oxide, KH-5500.5 parts of silane coupling agent, 2 parts of antibacterial agent from example 1 and 1680.2 parts of antioxidant for later use;
step two: uniformly mixing a thermoplastic polyurethane elastomer, aluminum oxide, a silane coupling agent KH-550, an antibacterial agent and an antioxidant 168 to obtain a mixture;
step three: and adding the mixture into an extruder for melt extrusion, and granulating to obtain the TPU plastic for the injection molding of the mobile phone protective sleeve.
Example 4:
the embodiment is a production process of TPU plastic for injection molding of a mobile phone protective sleeve, which comprises the following steps:
the method comprises the following steps: weighing 70 parts of thermoplastic polyurethane elastomer, 9 parts of boron nitride, KH-5601.5 parts of silane coupling agent, 8 parts of antibacterial agent from example 2 and 10101.0 parts of antioxidant for later use;
step two: uniformly mixing a thermoplastic polyurethane elastomer, boron nitride, a silane coupling agent KH-560, an antibacterial agent and an antioxidant 1010 to obtain a mixture;
step three: and adding the mixture into an extruder for melt extrusion, and granulating to obtain the TPU plastic for the injection molding of the mobile phone protective sleeve.
Comparative example 1:
comparative example 1 differs from example 1 in that no antimicrobial agent was added.
Comparative example 2:
comparative example 2 is an ABS and TPU composite antibacterial plastic alloy of application No. 201310319586.3.
The antibacterial performances of examples 3 to 4 and comparative examples 1 to 2 were examined, and the antibacterial test standards were as follows: QB/T2591-2003A & ltantibacterial plastic antibacterial property test method and antibacterial effect & gt. Detection bacteria: escherichia coli, Staphylococcus aureus.
Figure BDA0003447926870000141
Referring to the data in the table, according to the comparison between the embodiment and the comparative example 1, it can be known that the antibacterial property of the TPU plastic for injection molding of the mobile phone protective case can be greatly improved by adding the antibacterial agent, and according to the comparison between the embodiment and the comparative example 1, the TPU plastic disclosed by the invention has better antibacterial property and better antibacterial property than the antibacterial plastic in the prior art.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.

Claims (10)

1. The TPU plastic for injection molding of the mobile phone protective sleeve is characterized by comprising the following components in parts by weight:
50-70 parts of thermoplastic polyurethane elastomer, 4-9 parts of heat-conducting filler, 0.5-1.5 parts of coupling agent, 2-8 parts of antibacterial agent and 0.2-1.0 part of antioxidant;
the antibacterial agent is prepared by the following steps:
the method comprises the following steps: adding acetic anhydride and glacial acetic acid into a three-neck flask, dropwise adding a para-fluoroaniline solution while stirring, continuously stirring for reaction after dropwise adding, dropwise adding a mixed acid, continuously stirring for reaction after adding, pouring a reaction product into ice water after reaction, separating out a precipitate, performing suction filtration, and drying a filter cake to constant weight to obtain an intermediate 1;
step two: adding the intermediate 1 and a hydrochloric acid solution into a three-neck flask, heating to reflux reaction, pouring a reaction product into ice water after the reaction is finished, separating out a precipitate, performing suction filtration, washing a filter cake, and then drying to constant weight to obtain an intermediate 2;
step three: adding the intermediate 2, absolute ethyl alcohol and 8% palladium carbon into a reaction kettle, introducing hydrogen, continuously stirring for reaction, filtering a reaction product after the reaction is finished, and evaporating filtrate in a rotary manner to dryness to obtain an intermediate 3;
step four: adding the intermediate 3 and dichloromethane into a three-neck flask, adding triethylamine, stirring, dropwise adding a phosgene solution while stirring, continuing stirring for reaction after dropwise adding is finished, adding a reaction product into distilled water after the reaction is finished, precipitating, performing suction filtration, and drying a filter cake to constant weight to obtain an intermediate 4;
step five: adding terephthalyl alcohol and acetic anhydride into a four-neck flask, then dropwise adding hydrobromic acid while stirring, heating to reflux reaction after the dropwise addition is finished, adjusting the pH of a reaction product after the reaction is finished, separating out a solid, performing suction filtration, and drying a filter cake to constant weight to obtain an intermediate 5;
step six: adding the intermediate 4 and N, N-dimethylformamide into a three-neck flask, stirring, then adding potassium carbonate and the intermediate 5, then stirring at constant temperature for reaction, adding deionized water into a reaction product after the reaction is finished, then extracting, standing for liquid separation, and drying an organic phase to obtain an intermediate 6;
step seven: adding sodium, toluene and isoamylol into a four-neck flask, melting the sodium, stirring and dispersing to form sodium sand, then dropwise adding chlorobenzene while stirring, heating and stirring at constant temperature for reaction after dropwise adding, then dropwise adding phosphorus trichloride after cooling, heating and stirring at constant temperature for reaction after dropwise adding, filtering a reaction product while the reaction product is hot after the reaction is finished, rotationally evaporating filtrate, and then recrystallizing to obtain an intermediate 7;
step eight: adding the intermediate 6, the intermediate 7, hydroquinone and anhydrous acetonitrile into a three-neck flask, stirring for reaction, evaporating the reaction product to dryness in a rotating manner after the reaction is finished, and then recrystallizing to obtain the antibacterial agent.
2. The TPU plastic for injection molding of the mobile phone protective case according to claim 1, wherein the usage ratio of the acetic anhydride, the glacial acetic acid, the para-fluoroaniline solution and the mixed acid in the step one is 60 mL: 20mL of: 30g of: 10-15mL, wherein the para-fluoroaniline solution is a mixture of para-fluoroaniline and glacial acetic acid in a mass ratio of 1:1, and the mixed acid is a mixture of nitric acid and sulfuric acid in a volume ratio of 9-11: 1, the mass fraction of the nitric acid is 65-68%, and the mass fraction of the sulfuric acid is 95-98%.
3. The TPU plastic for injection molding of the mobile phone protective case according to claim 1, wherein the dosage ratio of the intermediate 1 and the hydrochloric acid solution in the second step is 0.01 mol: 120-150mL, and the molar concentration of the hydrochloric acid solution is 9 mol/L.
4. The TPU plastic for injection molding of mobile phone protective cases as claimed in claim 1, wherein the ratio of the amount of the intermediate 2, the palladium carbon 8% and the absolute ethyl alcohol in step three is 0.1 mol: 1.0-1.5 g: 100-.
5. The TPU plastic for injection molding of the mobile phone protective case according to claim 1, wherein the amount ratio of the intermediate 3, the dichloromethane, the triethylamine and the phosgene solution in the fourth step is 0.01 mol: 100mL of: 1.05-1.1 g: 30-40mL, the phosgene solution being phosgene in a ratio of 0.3 g: 10mL of a solution obtained by dissolving methylene chloride in water.
6. The TPU plastic for injection molding of mobile phone protective cases according to claim 1, wherein the dosage ratio of the terephthalyl alcohol, acetic anhydride and hydrobromic acid in the fifth step is 5.0 g: 80-90 mL: 25mL, and the mass fraction of the hydrobromic acid is 40%.
7. The TPU plastic for injection molding of the mobile phone protective case as claimed in claim 1, wherein the amount ratio of the intermediate 4, the N, N-dimethylformamide, the potassium carbonate, the intermediate 5 and the deionized water in the sixth step is 0.02 mol: 150mL of: 10 g: 0.07 mol: 100 mL.
8. The TPU plastic for injection molding of mobile phone protective sleeves as claimed in claim 1, wherein the amount ratio of the sodium, the toluene, the isoamyl alcohol, the chlorobenzene and the phosphorus trichloride in the seventh step is 0.25 mol: 100mL of: 1mL of: 20 g: 0.05 mol.
9. The TPU plastic for injection molding of the mobile phone protective case according to claim 1, wherein the amount ratio of the intermediate 6, the intermediate 7, hydroquinone and anhydrous acetonitrile in the step eight is 0.1 mol: 0.22 mol: 0.3-0.5 g: 100-.
10. The production process of the TPU plastic for injection molding of the mobile phone protective case according to claim 1 is characterized by comprising the following steps:
the method comprises the following steps: weighing 50-70 parts of thermoplastic polyurethane elastomer, 4-9 parts of heat-conducting filler, 0.5-1.5 parts of coupling agent, 2-8 parts of antibacterial agent and 0.2-1.0 part of antioxidant according to parts by weight for later use;
the heat-conducting filler is one or a mixture of more than two of magnesium oxide, aluminum oxide, silicon dioxide, boron nitride, aluminum nitride and silicon carbide in any proportion; the coupling agent is one of a silane coupling agent KH-550, a silane coupling agent KH-560 and a silane coupling agent KH-570; the antioxidant is one of antioxidant 168, antioxidant 1010 and antioxidant 1076;
step two: uniformly mixing a thermoplastic polyurethane elastomer, a heat-conducting filler, a coupling agent, an antibacterial agent and an antioxidant to obtain a mixture;
step three: and adding the mixture into an extruder for melt extrusion, and granulating to obtain the TPU plastic for the injection molding of the mobile phone protective sleeve.
CN202111654588.9A 2021-12-30 2021-12-30 TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof Withdrawn CN114213834A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111654588.9A CN114213834A (en) 2021-12-30 2021-12-30 TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111654588.9A CN114213834A (en) 2021-12-30 2021-12-30 TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof

Publications (1)

Publication Number Publication Date
CN114213834A true CN114213834A (en) 2022-03-22

Family

ID=80707075

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111654588.9A Withdrawn CN114213834A (en) 2021-12-30 2021-12-30 TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof

Country Status (1)

Country Link
CN (1) CN114213834A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117430941A (en) * 2023-10-10 2024-01-23 佛山市塑派科技有限公司 Purifying master batch for deodorizing antibacterial fresh-keeping product and preparation method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117430941A (en) * 2023-10-10 2024-01-23 佛山市塑派科技有限公司 Purifying master batch for deodorizing antibacterial fresh-keeping product and preparation method thereof
CN117430941B (en) * 2023-10-10 2024-05-14 佛山市塑派科技有限公司 Purifying master batch for deodorizing antibacterial fresh-keeping product and preparation method thereof

Similar Documents

Publication Publication Date Title
CN114213834A (en) TPU (thermoplastic polyurethane) plastic for injection molding of mobile phone protective sleeve and production process thereof
CN107312228A (en) It is a kind of for antibacterial matrices of vinyon and preparation method thereof
CN103012551B (en) Synthetic method of high-purity bortezomib and intermediate thereof
CN113493940B (en) Graphene thermal insulation fiber and preparation method thereof
CN103709643A (en) Antibacterial terylene master batch and preparation method thereof
CN107418133A (en) It is a kind of to exempt from spraying 3D printing consumptive material and preparation method thereof with antibacterial functions
CN107641250A (en) A kind of antibacterial matrices for polypropylene plastics and preparation method thereof
CN103435632B (en) A kind of preparation method of cefuroxime axetil
CN103059006A (en) Chrysin-1,2,3-triazole compound having antibacterial activity, and its preparation method
CN115197541A (en) Graphene-based antibacterial polyester master batch and preparation method thereof
CN113575575B (en) Film-coated drug-loaded microsphere, drug-sustained-release insect-expelling pet collar and preparation method thereof
Russo et al. Alginate/Polyvinylalcohol Blends for Agricultural Applications: Structure‐Properties Correlation, Mechanical Properties and Greenhouse Effect Evaluation
CN110591337A (en) High-performance TPU (thermoplastic polyurethane) film for glass interlayer and preparation method thereof
CN104788787A (en) Film material for greenhouse and preparation method of film material
CN113306258A (en) Slow-resilience polyurethane foam and preparation method thereof
CN101020628A (en) Preparation method of 2, 4-difluoro-3-hydroxybenzoic acid
CN104559158A (en) Preparation method of calcium sulfate whisker/nylon composite material
CN102417472A (en) Preparation method of florfenicol
CN109867639A (en) The method for preparing fumidil amido alcohol
CN109867637A (en) The preparation method of fumidil amido alcohol
CN109867640A (en) A kind of preparation method of fumidil amido alcohol
CN101723913A (en) O-substituted dioxazine compound with bactericidal activity, preparation method thereof and application thereof
CN208576173U (en) A kind of exhaust gas processing device
CN214483333U (en) A prevent bee clothes for bee kind is collected
CN112063132A (en) Antibacterial PBT plastic

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WW01 Invention patent application withdrawn after publication

Application publication date: 20220322

WW01 Invention patent application withdrawn after publication