CN106928702A - A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof - Google Patents

A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof Download PDF

Info

Publication number
CN106928702A
CN106928702A CN201511026604.4A CN201511026604A CN106928702A CN 106928702 A CN106928702 A CN 106928702A CN 201511026604 A CN201511026604 A CN 201511026604A CN 106928702 A CN106928702 A CN 106928702A
Authority
CN
China
Prior art keywords
polyphenylene oxide
area
parts
high temperature
temperature resistant
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.)
Pending
Application number
CN201511026604.4A
Other languages
Chinese (zh)
Inventor
杨桂生
李宗仁
赵冬云
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.)
Shanghai Genius Advanced Materials Group Co Ltd
Original Assignee
Shanghai Genius Advanced Materials Group 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 Shanghai Genius Advanced Materials Group Co Ltd filed Critical Shanghai Genius Advanced Materials Group Co Ltd
Priority to CN201511026604.4A priority Critical patent/CN106928702A/en
Publication of CN106928702A publication Critical patent/CN106928702A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L77/00Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Compositions of derivatives of such polymers
    • C08L77/06Polyamides derived from polyamines and polycarboxylic acids
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25Component parts, details or accessories; Auxiliary operations
    • B29C48/92Measuring, controlling or regulating
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2948/00Indexing scheme relating to extrusion moulding
    • B29C2948/92Measuring, controlling or regulating
    • B29C2948/92504Controlled parameter
    • B29C2948/9258Velocity
    • B29C2948/9259Angular velocity
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C2948/00Indexing scheme relating to extrusion moulding
    • B29C2948/92Measuring, controlling or regulating
    • B29C2948/92504Controlled parameter
    • B29C2948/92704Temperature
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2201/00Properties
    • C08L2201/08Stabilised against heat, light or radiation or oxydation

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Compositions Of Macromolecular Compounds (AREA)

Abstract

The invention provides a kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof, composite contains:30-50 parts of high temperature resistant nylon, 10-40 parts of polyphenylene oxide, 5-40 parts of mineral filler, 3-5 parts of compatilizer, 0.5-1 parts of coupling agent, 0.5-1 parts of antioxidant and 0.5-1 parts of lubricant;Preparation method includes:30-50 parts of high temperature resistant nylon, 10-40 parts of polyphenylene oxide, 5-25 parts of mineral filler, 3-5 parts of compatilizer, 0.5-1 parts of coupling agent, 0.5-1 parts of antioxidant, 0.5-1 parts of mix lubricant is uniform, obtain mixture;Mixture is added in double screw extruder from main spout, 0-15 parts of mineral filler is added in the double screw extruder from side spout, by obtaining high temperature resistant nylon/polyphenylene oxide composite material after tie rod, cooling, pelletizing and drying;High temperature resistant nylon/polyphenylene oxide composite material of the invention has the advantages that excellent heat resistance, high rigidity, good apparent mass, preferable mobility, easy-formation are processed.

Description

A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof
Technical field
The invention belongs to technical field of polymer composite materials, it is related to a kind of nylon/polyphenylene oxide composite material and preparation method thereof.
Background technology
High temperature resistant nylon product mainly including 6T, 6I, 9T, 9I, 10T, 10I, the 12T in semiaromatic polyamide composition etc., be by Dicarboxylic acids and aliphatic diamine with aromatic ring are through prepared by melt polycondensation, it in polyamide molecule main chain due to introducing fragrance Ring, so as to improve heat resistance and mechanical property, reduces water absorption rate, is between general engineering plastic nylon and high temperature resistant engineering Heat resistance between plastics PEEK resin high.Because semi-aromatic nylon is compared with nylon66 fiber, its maximum advantage is heat-resisting The excellent and relatively low water absorption rate of property;Meanwhile, compared with all aromatic nylon, it has processing fluidity good, the spy being easily worked Property.Therefore, as the need for the developing rapidly with environmental protection cause of new and high technology, its market demand is in rising trend, its application is opened Hair also has new progress.
Polyphenylene oxide (abbreviation PPE or PPO) have good mechanical property, chemical stability, dielectric properties, heat resistance and Anti-flammability, is a kind of high performance thermoplastic engineering plastic.First generation modified polyphenyl ether product is released since GE companies within 1966 Afterwards, polyphenylene oxide industry is developed rapidly, has become the fourth-largest engineering plastics after PA, PC, POM.Non-modified polyphenylene oxide With good mechanical property, heat resistance, dimensional stability, chemical stability, hydrolytic resistance, high rigidity and anti-flammability etc., But PPO molecule chain rigiditys are larger, and notch shock is very sensitive, simultaneously because its melt viscosity higher, prevents it from being molded Shaping, therefore significantly limit its application.
Because polyphenylene oxide is armorphous and nonpolar resin, nylon is crystal type and polar resin, while the two has breach Sensitivity, the poor defect of impact property, therefore, how to produce one kind can either comprehensive polyphenylene oxide and semi-aromatic nylon each Advantage can overcome the alloy material of the poor defect of the shock resistance of the two just to turn into problem demanding prompt solution again.
The content of the invention
First purpose of the invention is to provide a kind of high temperature resistant nylon/polyphenylene oxide composite material.
Second object of the present invention is to provide a kind of preparation method of above-mentioned high temperature resistant nylon/polyphenylene oxide composite material.
To reach above-mentioned purpose, solution of the invention is:
A kind of high temperature resistant nylon/polyphenylene oxide composite material, it is characterised in that:Weight portion containing following components and every kind of component is such as Under:
Wherein, above-mentioned high temperature resistant nylon can be semi-aromatic nylon, can be further selected from PA6T, PA6I, PA9T, PA9I, Any one or a few in PA10T, PA12T and PA13T.
Above-mentioned polyphenylene oxide can be the homopolymers (such as LXR038) containing 2,6- dimethyl benzene ether units, or be to contain 2,6- The copolymer of dimethyl benzene ether unit and 2,3,6- trimethyl -1,4- phenylene ether units.The weight portion of polyphenylene oxide can also be preferably 10-25 Part.
Above-mentioned compatilizer can be selected from maleic acid, maleic anhydride, fumaric acid, itaconic acid, glycidyl acrylate and lemon Any one or a few in acid.
Above-mentioned coupling agent can be selected from VTES, gamma-aminopropyl-triethoxy-silane, γ-aminopropyl trimethoxy Silane, γ-propyl methacrylate base silane, γ-glycidyl ether oxygen propyl trimethoxy silicane, positive tetraisopropyl titanate and isopropyl Any one or a few in the different 18 acyl titanate esters of base three.
Above-mentioned mineral filler can be inorganic mineral filler, can be further selected from mica, wollastonite, talcum powder, calcium carbonate, Any one or a few in barium sulfate or kaolin.The weight portion of mineral filler can also be preferably 20-40 parts.
Above-mentioned antioxidant can be phenolic antioxidant, can be further selected from four [β-(3,5- di-tert-butyl-hydroxy phenyl) third Acid] pentaerythritol ester, β-positive octadecanol ester of (3,5- di-tert-butyl-hydroxy phenyls) propionic acid and the (the 4- tert-butyl groups -3- of 1,3,5- tri- Hydroxyl -2,6- dimethyl benzyls) any one or a few in -1,3,5- triazines -2,4,6- (1H, 3H, 5H)-triketone.
Above-mentioned lubricant can be fatty acid amide series lubricant agent, can be further selected from N, N '-bis- ethylene hard fatty acids acid amides, Any one or a few in stearic amide, oleamide, zinc stearate and calcium stearate.
A kind of preparation method of above-mentioned high temperature resistant nylon/polyphenylene oxide composite material, it comprises the following steps:
(1), by 30-50 parts of dry high temperature resistant nylon, 10-40 parts of dry polyphenylene oxide, 5-25 parts of dry mineral filler, 3-5 parts of compatilizer, 0.5-1 parts of coupling agent, 0.5-1 parts of antioxidant, 0.5-1 parts of lubricant are well mixed in high-speed mixer, obtain To mixture;
(2), mixture is added in the double screw extruder from the main spout of double screw extruder, it is dry by 0-15 parts Mineral filler is added in the double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and dry High temperature resistant nylon/polyphenylene oxide composite material is obtained after dry.
Wherein, in step (1), the forced air drying 6-8 at 100-120 DEG C is small by high temperature resistant nylon for dry high temperature resistant nylon When gained;Dry polyphenylene oxide is polyphenylene oxide at 100-110 DEG C obtained by forced air drying 6-8 hours;Dry mineral filler is ore deposit Thing filler is at 110-130 DEG C obtained by forced air drying 6-8 hours.
In step (1), the rotating speed of high-speed mixer can be 600-800r/min, and the time of mixing can be 5-10min.
In step (2), double screw extruder is 295 ± 10 DEG C using zone temperature control, area's temperature, and two area's temperature are 295 ± 10 DEG C, three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, and five area's temperature are 315 ± 10 DEG C, and six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, and eight area's temperature are 310 ± 10 DEG C, and nine area's temperature are 305 ± 10 DEG C, and ten area's temperature are 305 ± 10 DEG C, head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
In the preparation method of high temperature resistant nylon/polyphenylene oxide composite material of the invention, mineral filler can be added at twice, every time The species of the mineral filler of addition can be with identical, it is also possible to different.Because the particle diameter of mineral filler is smaller, bulk density is higher, In with other component Blending Processes, if too high levels, mineral filler is easily deposited on feed hopper bottom, causes feeding uneven; If all entered from side spout, because side spout is closer to the distance apart from die head, mineral filler is blended with other component melts Time shortens, and is easily caused mixing heterogeneity, and properties of product are deteriorated, so consider preferably adding in two steps.
Due to using such scheme, the beneficial effects of the invention are as follows:
Firstth, the mineral filler that the present invention is used selects the inorganic rigid particle of acid-fast alkali-proof, water insoluble and organic solvent, tool There is fabulous photostability and weatherability, there is the fabulous rheological equationm of state in height filling, hardly wear and tear gold in process Category, therefore, coming filling-modified high temperature resistant nylon and polyphenylene oxide double substrate material using the mineral filler can improve its intensity, firm Property, improve the crystalline rate and crystallinity of product, so as to improve heat resistance and dimensional stability.
Secondth, high temperature resistant nylon of the invention/polyphenylene oxide composite material adds the preferable high temperature resistant nylon of mobility, improves polyphenyl The mobility of ether, so that product has the advantages that to have good apparent mass, good processability and is molded fast.3rd, this hair High temperature resistant nylon strand mutually interts with the strand of polyphenylene oxide and tangles in bright high temperature resistant nylon/polyphenylene oxide composite material so that Product has preferable toughness and notched impact properties.
Specific embodiment
The present invention relates to a kind of high temperature resistant nylon/polyphenylene oxide composite material and its preparation method and application.
<High temperature resistant nylon/polyphenylene oxide composite material>
High temperature resistant nylon/polyphenylene oxide composite material of the invention contains following components and the weight portion of every kind of component is as follows:
Wherein, high temperature resistant nylon of the invention can be semi-aromatic nylon, and the semi-aromatic nylon can be more preferably Any one or a few in PA6T, PA6I, PA9T, PA9I, PA10T, PA12T and PA13T.Different semi-aromatic nylons 1.8MPa under heat distortion temperature between 260-290 DEG C.
Polyphenylene oxide can be selected from and contain the homopolymers of 2,6- dimethyl benzene ether units, or selected from contain 2,6- dimethyl benzenes ether unit and The copolymer of 2,3,6- trimethyl -1,4- phenylene ether units.Polyphenylene oxide can be preferably to be produced by China LanXing Chemical Group and provide, board Number be PPO LXR038.
Compatilizer can be selected from maleic acid, maleic anhydride, fumaric acid, itaconic acid, glycidyl acrylate and citric acid Any one or a few.
Coupling agent can selected from for VTES, gamma-aminopropyl-triethoxy-silane, γ-aminopropyltrimethoxysilane, γ-propyl methacrylate base silane, γ-glycidyl ether oxygen propyl trimethoxy silicane, positive tetraisopropyl titanate and isopropyl three are different Any one or a few in 18 acyl titanate esters.
Mineral filler can be inorganic mineral filler, and the inorganic mineral filler can be preferably mica, wollastonite, talcum powder, carbon Any one or a few in sour calcium, barium sulfate or kaolin.The average grain diameter of inorganic mineral filler is 0.4-20 μm.Antioxidant Can be phenolic antioxidant, the phenolic antioxidant can be preferably four [β-(3,5- di-tert-butyl-hydroxy phenyl) propionic acid] Ji Wusi Alcohol ester, β-positive octadecanol ester of (3,5- di-tert-butyl-hydroxy phenyls) propionic acid and the (the 4- tert-butyl group -3- hydroxyls -2,6- two of 1,3,5- tri- Methyl-benzyl) any one or a few in -1,3,5- triazines -2,4,6- (1H, 3H, 5H)-triketone.
Lubricant can be fatty acid amide series lubricant agent, and the fatty acid amide series lubricant agent can be preferably N, and N '-bis- ethylenes are hard Any one or a few in fatty acid amide, stearic amide, oleamide, zinc stearate and calcium stearate.
<The preparation method of high temperature resistant nylon/polyphenylene oxide composite material>
The preparation method of high temperature resistant nylon/polyphenylene oxide composite material of the invention comprises the following steps:
(1), by 30-50 parts of dry high temperature resistant nylon, 10-40 parts of dry polyphenylene oxide, 5-25 parts of dry mineral filler, 3-5 parts of compatilizer, 0.5-1 parts of coupling agent, 0.5-1 parts of antioxidant and 0.5-1 parts of lubricant are well mixed in high-speed mixer, Obtain mixture;
(2), mixture is added in the double screw extruder from the main spout of double screw extruder, it is dry by 0-15 parts Mineral filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying Deng obtaining high temperature resistant nylon/polyphenylene oxide composite material after post-processing step.
Wherein, in step (1), dry high temperature resistant nylon is by high temperature resistant nylon forced air drying 6-8 hours at 100-120 DEG C Gained;Dry polyphenylene oxide is polyphenylene oxide at 100-110 DEG C obtained by forced air drying 6-8 hours;Dry mineral filler is mineral Filler is at 110-130 DEG C obtained by forced air drying 6-8 hours.
In step (1), the rotating speed of high-speed mixer can be 600-800r/min, and the time of mixing can be 5-10min.
In step (2), double screw extruder is 295 ± 10 DEG C using zone temperature control, area's temperature, and two area's temperature are 295 ± 10 DEG C, three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, and five area's temperature are 315 ± 10 DEG C, six area's temperature It it is 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature are 305 ± 10 DEG C, ten area's temperature It is 305 ± 10 DEG C to spend, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
One area's temperature is equal to two area's temperature.Three area's temperature, four area's temperature and five area's temperature then gradually rise, i.e. five area's temperature>4th area Temperature>Three area's temperature, it is preferable that five+10 DEG C of temperature=tetra- area of area temperature, four+10 DEG C of temperature=tri- area of area temperature.Five area's temperature, Six area's temperature and seven area's temperature are equal.Seven area's temperature, eight area's temperature and nine area's temperature are gradually reduced again, i.e. seven area's temperature>Eight area's temperature Degree>Nine area's temperature, it is preferable that seven+5 DEG C of temperature=eight area of area temperature, eight+5 DEG C of temperature=nine area of area temperature.Nine area's temperature, tenth area Temperature and head temperature are equal, i.e. nine temperature=ten area of area temperature=head temperature.Above each area's temperature gradually rises, and can make Temperature of charge progressivelyes reach suitable processing temperature, behind cause that temperature of charge continues to raise due to screw rod shearing, so reducing each Area's temperature avoids that temperature of charge is too high to cause material to thermally decompose.
In the preparation method of high temperature resistant nylon/polyphenylene oxide composite material of the invention, mineral filler can be added at twice, every time The species of the mineral filler of addition can be with identical, it is also possible to different.The weight portion of the second dry mineral filler for adding can be with Preferably 1-15 parts.
<The application of high temperature resistant nylon/polyphenylene oxide composite material>
High temperature resistant nylon/polyphenylene oxide composite material of the invention can be applied in electronic apparatus industry (such as auto industry), Such as it is used to prepare the high temperature resistant component in automobile.
<Embodiment>
Embodiment one
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 1 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment one of table 1
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 20 parts of dry polyphenylene oxide, 25 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 15 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment two
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 2 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment two of table 2
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 30 parts of dry polyphenylene oxide, 20 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 10 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment three
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 3 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment three of table 3
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 30 parts of dry polyphenylene oxide, 20 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), by mixture from the main spout of double screw extruder be added to the double screw extruder in (double screw extruder Mineral filler is added without in side spout), by obtaining high temperature resistant nylon after the post-processing steps such as tie rod, cooling, pelletizing and drying / polyphenylene oxide composite material.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Example IV
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 4 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the example IV of table 4
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 50 parts of dry high temperature resistant nylons, 10 parts of dry polyphenylene oxide, 25 parts of dry mineral fillers, 5 parts of phases Hold agent, 1 part of coupling agent, 1 part of antioxidant and 1 part of lubricant to be well mixed in high-speed mixer, the rotating speed of the high-speed mixer It is 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 15 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment five
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 5 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment five of table 5
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 8h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 30 parts of dry high temperature resistant nylons, 30 parts of dry polyphenylene oxide, 25 parts of dry mineral fillers, 5 parts of phases Hold agent, 1 part of coupling agent, 1 part of antioxidant and 1 part of lubricant to be well mixed in high-speed mixer, the rotating speed of the high-speed mixer It is 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 15 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment six
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 6 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment six of table 6
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 20 parts of dry polyphenylene oxide, 25 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 15 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment seven
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 7 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment seven of table 7
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 30 parts of dry polyphenylene oxide, 20 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), mixture is added in the double screw extruder from the main spout of double screw extruder, by 10 parts of dry ore deposits Thing filler is added in double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and drying etc. High temperature resistant nylon/polyphenylene oxide composite material is obtained after post-processing step.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
Embodiment eight
The constituent content of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment is as shown in table 8 below:
The constituent content table of the high temperature resistant nylon/polyphenylene oxide composite material of the embodiment eight of table 8
The preparation method of the high temperature resistant nylon/polyphenylene oxide composite material of the present embodiment comprises the following steps:
(1), by high temperature resistant nylon, polyphenylene oxide and mineral filler respectively at air blast in 110 DEG C, 105 DEG C and 120 DEG C of drying box 6h is dried, dry high temperature resistant nylon, dry polyphenylene oxide and dry mineral filler is obtained;
(2), by 40 parts of dry high temperature resistant nylons, 30 parts of dry polyphenylene oxide, 20 parts of dry mineral fillers, 4 parts of phases Hold agent, 0.5 part of coupling agent, 0.5 part of antioxidant and 0.5 part of lubricant to be well mixed in high-speed mixer, the high-speed mixer Rotating speed be 650r/min, incorporation time is 8min, obtains mixture;
(3), by mixture from the main spout of double screw extruder be added to the double screw extruder in ((double screw extruder Mineral filler is added without in side spout)), by obtaining high temperature resistant Buddhist nun after the post-processing steps such as tie rod, cooling, pelletizing and drying Dragon/polyphenylene oxide composite material.
Wherein, in step (3), double screw extruder is respectively using zone temperature control, each area's temperature:One area's temperature is 295 ± 10 DEG C, two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, and four area's temperature are 305 ± 10 DEG C, five area's temperature It it is 315 ± 10 DEG C, six area's temperature are 315 ± 10 DEG C, seven area's temperature are 315 ± 10 DEG C, eight area's temperature are 310 ± 10 DEG C, nine area's temperature It is 305 ± 10 DEG C to spend, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, 250-350 revs/min of screw speed.
High temperature resistant nylon/polyphenylene oxide composite material to embodiment one to embodiment eight carries out property measure, as a result as shown in table 9.
The embodiment one of table 9 to the property of the high temperature resistant nylon/polyphenylene oxide composite material of embodiment eight determines table
Performance Tensile strength Bending strength Bending modulus Izod notch impact strengths HDT
Method of testing ASTM D638 ASTM D790 ASTM D790 ASTM D256 ISO 75‐2
Unit MPa MPa MPa KJ/m2
Embodiment one 142 258 11431 17 281
Embodiment two 135 251 10078 15 278
Embodiment three 130 246 9878 12 272
Example IV 85 257 11628 18 285
Embodiment five 126 263 11342 15 281
Embodiment six 109 251 11453 17 274
Embodiment seven 123 248 10827 15 277
Embodiment eight 138 233 9724 12 262
The above-mentioned description to embodiment is to be understood that and use the present invention for ease of those skilled in the art.It is familiar with The personnel of art technology obviously can easily make various modifications to these embodiments, and should General Principle described herein Use in other embodiment without by performing creative labour.Therefore, the invention is not restricted to above-described embodiment, art technology Personnel's announcement of the invention, does not depart from improvement that scope made and modification all should be in protection scope of the present invention Within.

Claims (10)

1. a kind of high temperature resistant nylon/polyphenylene oxide composite material, it is characterised in that:Weight portion containing following components and every kind of component It is as follows:
2. high temperature resistant nylon/polyphenylene oxide composite material according to claim 1, it is characterised in that:The high temperature resistant nylon is Semi-aromatic nylon;
Preferably, the semi-aromatic nylon is selected from appointing in PA6T, PA6I, PA9T, PA9I, PA10T, PA12T and PA13T Anticipate one or more.
3. high temperature resistant nylon/polyphenylene oxide composite material according to claim 1, it is characterised in that:The polyphenylene oxide be containing The homopolymers of 2,6- dimethyl benzene ether units, or be to contain 2,6- dimethyl benzenes ether unit and 2,3,6- trimethyls-Isosorbide-5-Nitrae-phenylene ether units Copolymer;And/or,
The compatilizer is selected from appointing in maleic acid, maleic anhydride, fumaric acid, itaconic acid, glycidyl acrylate and citric acid Anticipate one or more;And/or,
Described coupling agent be selected from VTES, gamma-aminopropyl-triethoxy-silane, γ-aminopropyltrimethoxysilane, γ-propyl methacrylate base silane, γ-glycidyl ether oxygen propyl trimethoxy silicane, positive tetraisopropyl titanate and isopropyl three are different Any one or a few in 18 acyl titanate esters.
4. high temperature resistant nylon/polyphenylene oxide composite material according to claim 1, it is characterised in that:The mineral filler is nothing Machine mineral filler;
Preferably, the mineral filler is selected from any one in mica, wollastonite, talcum powder, calcium carbonate, barium sulfate or kaolin Plant or several.
5. high temperature resistant nylon/polyphenylene oxide composite material according to claim 1, it is characterised in that:The antioxidant is phenols Antioxidant;
Preferably, the antioxidant is selected from four [β-(3,5- di-tert-butyl-hydroxy phenyl) propionic acid] pentaerythritol esters, β-(3,5- Di-tert-butyl-hydroxy phenyl) the positive octadecanol ester of propionic acid and 1,3,5- tri- (the 4- tert-butyl group -3- hydroxyl -2,6- dimethyl benzyls) -1,3,5- Any one or a few in triazine -2,4,6- (1H, 3H, 5H)-triketone.
6. high temperature resistant nylon/polyphenylene oxide composite material according to claim 1, it is characterised in that:The lubricant is fat Sour acid amides series lubricant agent;
Preferably, the lubricant is selected from N, N '-bis- ethylene hard fatty acids acid amides, stearic amide, oleamide, zinc stearate With any one or a few in calcium stearate.
7. a kind of preparation method of high temperature resistant nylon/polyphenylene oxide composite material as described in any in claim 1 to 6, its feature It is:Comprise the following steps:
(1), by 30-50 parts of dry high temperature resistant nylon, 10-40 parts of dry polyphenylene oxide, 5-25 parts of dry mineral filler, 3-5 parts of compatilizer, 0.5-1 parts of coupling agent, 0.5-1 parts of antioxidant, 0.5-1 parts of lubricant are well mixed in high-speed mixer, obtain To mixture;
(2), the mixture is added in the double screw extruder from the main spout of double screw extruder, it is dry by 0-15 parts Dry mineral filler is added in the double screw extruder from the side spout of double screw extruder, by tie rod, cooling, pelletizing and High temperature resistant nylon/polyphenylene oxide composite material is obtained after drying.
8. preparation method according to claim 7, it is characterised in that:The dry high temperature resistant nylon is by high temperature resistant nylon At 100-120 DEG C obtained by forced air drying 6-8 hours;And/or,
The dry polyphenylene oxide is polyphenylene oxide at 100-110 DEG C obtained by forced air drying 6-8 hours;And/or,
The dry mineral filler is mineral filler at 110-130 DEG C obtained by forced air drying 6-8 hours.
9. preparation method according to claim 7, it is characterised in that:In step (1), the high-speed mixer turn Speed is 600-800r/min;And/or,
In step (1), the time of the high-speed mixer mixing is 5-10min.
10. preparation method according to claim 7, it is characterised in that:In step (2), the double screw extruder is adopted Zone temperature control is used, area's temperature is 295 ± 10 DEG C, and two area's temperature are 295 ± 10 DEG C, and three area's temperature are 300 ± 10 DEG C, 4th area Temperature is 305 ± 10 DEG C, and five area's temperature are 315 ± 10 DEG C, and six area's temperature are 315 ± 10 DEG C, and seven area's temperature are 315 ± 10 DEG C, 8th area Temperature is 310 ± 10 DEG C, and nine area's temperature are 305 ± 10 DEG C, and ten area's temperature are 305 ± 10 DEG C, and head temperature is 305 ± 10 DEG C, screw rod 250-350 revs/min of rotating speed.
CN201511026604.4A 2015-12-31 2015-12-31 A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof Pending CN106928702A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201511026604.4A CN106928702A (en) 2015-12-31 2015-12-31 A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201511026604.4A CN106928702A (en) 2015-12-31 2015-12-31 A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof

Publications (1)

Publication Number Publication Date
CN106928702A true CN106928702A (en) 2017-07-07

Family

ID=59442719

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201511026604.4A Pending CN106928702A (en) 2015-12-31 2015-12-31 A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof

Country Status (1)

Country Link
CN (1) CN106928702A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109535712A (en) * 2018-11-28 2019-03-29 广东威林工程塑料股份有限公司 A kind of MXD6, biology base nylon, polyphenylene oxide alloy composite material and preparation method
CN110157176A (en) * 2019-06-20 2019-08-23 山东东辰瑞森新材料科技有限公司 A kind of PPO/PA composite material and preparation method
WO2021079916A1 (en) * 2019-10-21 2021-04-29 旭化成株式会社 Reinforced resin composition, molded article and method for improving tensile strength at high temperatures

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101305051A (en) * 2005-11-10 2008-11-12 旭化成化学株式会社 Resin composition having excellent flame retardance
CN101724252A (en) * 2009-12-18 2010-06-09 上海金发科技发展有限公司 Semi-aromatic nylon and polyphenyl ether alloy
CN103333490A (en) * 2013-06-13 2013-10-02 江苏安格特科技发展有限公司 Low gloss, high impact and high temperature resistance nylon alloy material and preparation method thereof
CN104419195A (en) * 2013-08-21 2015-03-18 上海杰事杰新材料(集团)股份有限公司 Inorganic mineral filled semi-aromatic nylon composite material and preparation method thereof
CN104448809A (en) * 2013-09-25 2015-03-25 上海杰事杰新材料(集团)股份有限公司 Glass fiber/mineral composite enhanced modified semi-aromatic nylon material and preparation method thereof
CN105392841A (en) * 2013-06-03 2016-03-09 普立万公司 Flame retardant high temperature nylon

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101305051A (en) * 2005-11-10 2008-11-12 旭化成化学株式会社 Resin composition having excellent flame retardance
CN101724252A (en) * 2009-12-18 2010-06-09 上海金发科技发展有限公司 Semi-aromatic nylon and polyphenyl ether alloy
CN105392841A (en) * 2013-06-03 2016-03-09 普立万公司 Flame retardant high temperature nylon
CN103333490A (en) * 2013-06-13 2013-10-02 江苏安格特科技发展有限公司 Low gloss, high impact and high temperature resistance nylon alloy material and preparation method thereof
CN104419195A (en) * 2013-08-21 2015-03-18 上海杰事杰新材料(集团)股份有限公司 Inorganic mineral filled semi-aromatic nylon composite material and preparation method thereof
CN104448809A (en) * 2013-09-25 2015-03-25 上海杰事杰新材料(集团)股份有限公司 Glass fiber/mineral composite enhanced modified semi-aromatic nylon material and preparation method thereof

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109535712A (en) * 2018-11-28 2019-03-29 广东威林工程塑料股份有限公司 A kind of MXD6, biology base nylon, polyphenylene oxide alloy composite material and preparation method
CN110157176A (en) * 2019-06-20 2019-08-23 山东东辰瑞森新材料科技有限公司 A kind of PPO/PA composite material and preparation method
WO2021079916A1 (en) * 2019-10-21 2021-04-29 旭化成株式会社 Reinforced resin composition, molded article and method for improving tensile strength at high temperatures
JPWO2021079916A1 (en) * 2019-10-21 2021-04-29
CN114207035A (en) * 2019-10-21 2022-03-18 旭化成株式会社 Reinforced resin composition, molded article, and method for improving tensile strength at high temperature
JP7223159B2 (en) 2019-10-21 2023-02-15 旭化成株式会社 REINFORCED RESIN COMPOSITION, MOLDED PRODUCT AND METHOD FOR IMPROVING TENSILE STRENGTH AT HIGH TEMPERATURE

Similar Documents

Publication Publication Date Title
CN102585478B (en) Toughened polyphenyl ether and nylon alloy and preparation method for toughened polyphenyl ether and nylon alloy
EP3789456B1 (en) Polyamide resin composition having high metal texture and preparation method of polyamide resin composition
CN102276982B (en) Polyphenylene sulfide and high-temperature-resistant nylon complex and preparation method thereof
CN106947247A (en) Composite modified semi-aromatic nylon/polyphenylene oxide composite material of glass fibre-mineral and preparation method thereof
CN101792596A (en) Composite material for recycling waste vehicle nylon products and preparation method thereof
CN102391607A (en) Polylactic acid/styrene resin composition and preparation method thereof
CN106046776A (en) High flow carbon fiber reinforced nylon composite material with fine surface and preparation method thereof
CN111087782A (en) Flame-retardant PCABS composition
CN108034204A (en) A kind of low-temperature impact-resistant polymer blend and preparation method thereof
CN106928702A (en) A kind of high temperature resistant nylon/polyphenylene oxide composite material and preparation method thereof
CN109280322A (en) A kind of ultra-toughness POK polyketone material and preparation method thereof
CN105086452B (en) A kind of halogen-free flameproof polyphenyl thioether composite material and preparation method thereof
CN113956643B (en) Chemical-resistant scratch-resistant high-hardness PCPBT (Poly-p-phenylene terephthamide) composite material and preparation method thereof
CN107513255A (en) A kind of 3D printing toughness reinforcing heat-resisting PET material and preparation method thereof
CN102942736B (en) High-glass fiber content reinforced polypropylene material and preparation method thereof
CN102532694A (en) Composite material with high melt index and preparation method thereof
CN105419292A (en) High-toughness PC/PBT alloy material and preparation method thereof
CN109385063B (en) Wear-resistant PC/ASA alloy material and preparation method thereof
CN112679931B (en) PC/ABS and regenerated PCTG composite material for electric meter box and preparation method thereof
CN110862684A (en) POK/PPS composite material and preparation method thereof
CN111171541A (en) Modified PC/ABS composition for 3D printing and preparation method thereof
CN105968801A (en) High-performance modified polyamide composite material and preparation method thereof
CN113174131A (en) Low-moisture-absorption high-wear-resistance PK/PA66 alloy and preparation method thereof
CN103571182A (en) High-fluidity toughened filling nylon and preparation method thereof
CN112662143A (en) PBT composition with high elongation at break and preparation method thereof

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
RJ01 Rejection of invention patent application after publication

Application publication date: 20170707

RJ01 Rejection of invention patent application after publication