Summary of the invention
Problem to be solved by this invention is to propose a kind of self-lubricating high-strength pouring nylon preparation method for above-mentioned prior art, adopt caprolactam monomer and modified Nano Material cladding under the vacuum anhydrous condition, to make the nylon performed polymer through base catalysis, and directly casting obtains self-lubricating high-strength pouring nylon parts, the cast nylon parts that obtain, frictional coefficient is little, can solve the high-wear resistance of the parts of nylon; Because intensity is high, range of application is wider simultaneously.
The present invention solves the problems of the technologies described above the solution that adopts to be: the preparation method of self-lubricating high-strength pouring nylon is characterized in that including following steps:
1) gets the caprolactam monomer of 1000 parts of mass fractions, the nano-TiO that the surface modification of mass fraction 1-20 part is crossed
2The Nano graphite powder of crossing with the basic treatment of mass fraction 1-50 part, join in the reactor, stirring also heats to 120 ℃-140 ℃, vacuumize simultaneously, make the reactor internal gas pressure be lower than 500Pa, continue to stir the hexanolactam melted blend 20-60 minute, obtain containing the hexanolactam melt of nano composite material;
2) sodium hydrate solid with massfraction 2-8 part joins step 1) in the hexanolactam melt that contains nano composite material that obtains, keep the reactor internal gas pressure to be lower than 500Pa, be warmed up to 140-150 ℃, continue to stir 20-60 minute, obtain the alkaline caprolactam melted blend;
3) logical nitrogen recovers reactor pressure to normal atmosphere in reactor, under the violent stirring condition with the 3-isocyanic ester methylene-3 of massfraction 2-8 part, 5,5-3-methyl cyclohexanol based isocyanate (IPDI) or tolylene diisocyanate (TDI) join step 2) in the alkaline caprolactam melted blend of gained, stir, be warming up to simultaneously 140-155 ℃, obtain hexanolactam nylon performed polymer;
4) casting mold is preheating to 165-190 ℃ and constant temperature in heating container, with step 3) gravity flow of the hexanolactam nylon performed polymer that obtains or pressurization inject in the mold cavity, the follow-up continuation of insurance temperature of close die 10-120 minute, then naturally cool to room temperature, namely obtain the self-lubricating high-strength pouring nylon parts of forming.
Press such scheme, described nano-TiO
2Surface modifying treatment be: with nano-TiO
2Join in the dehydrated alcohol, rapid stirring is even, obtains TiO
2The dehydrated alcohol mixture; Getting KH-550 or KH-50 coupling agent is dissolved in a small amount of water and and TiO
2The dehydrated alcohol mixture mix, stirred 4-6 hour at 40-60 ℃, the system centrifugation obtains lower floor's paste, puts into baking oven 80-100 ℃ dry for standby.
Press such scheme, the basic treatment method of described Nano graphite powder is: with the technical grade Nano graphite powder in the sodium hydroxide solution of mass percent concentration 10-30%, 20-70 ℃ of lower the immersion after 12-24 hour filtered, and the Nano graphite powder that obtains is 100-150 ℃ of dry for standby in baking oven.
Reaction principle of the present invention is as follows:
(1) sodium hydroxide becomes negative ion with the initiation hexanolactam
(2) IPDI or TDI promoting agent and hexanolactam form imide structure
(3) imide structure transfer reaction
The characteristics of self-lubricating high-strength pouring nylon of comparing the present invention preparation with existing cast nylon are as follows:
It is low that the cast nylon of the present invention preparation has a frictional coefficient, and inner nano-graphite self-lubricating need not to add lubricant as moving parts, has self-lubricating function.By the intensity of nano-material surface effect and coupling effect raising nylon, to compare with ultimate compression strength, the tensile strength of common nylon, intensity has improved more than 20%, and frictional coefficient has reduced more than 60%.
The self-lubricating high-strength pouring nylon the key technical indexes of the present invention's preparation is as follows:
1. density 1.12-1.2g/cm
3
2. ultimate compression strength: 110-130MPa
3. tensile strength: 85-105MPa
4. elongation at break: 25-30%
5. flexural strength: 100-110MPa
6. shock strength: 6.5-8.5kJ/m
2
7. frictional coefficient: 0.1-0.12
Self-lubricating high-strength pouring nylon preparation method of the present invention has that process unit equipment is simple, and operational path is simple and direct, and moulding control is simple, part dimension, the unconfined advantage of shape.
Embodiment
Following for embodiment will help to understand the present invention:
Embodiment 1:
With the 20g nano-TiO
2Join in the 80ml dehydrated alcohol, rapid stirring is even, obtains TiO
2The dehydrated alcohol mixture; Getting 1g KH-550 coupling agent is dissolved in the 20ml water and and TiO
2The dehydrated alcohol mixture mix, stirred 4 hours at 60 ℃, the system centrifugation obtains lower floor's paste, puts into 90 ℃ of oven dry of baking oven, grinds 400 mesh sieves, obtains the nano-TiO that surface modification is crossed
2
Embodiment 2:
With the 100g nano-TiO
2Join in the 500ml dehydrated alcohol, rapid stirring is even, obtains TiO
2The dehydrated alcohol mixture; Getting 4g KH-50 coupling agent is dissolved in the 50ml water and and TiO
2The dehydrated alcohol mixture mix, stirred 6 hours at 50 ℃, the system centrifugation obtains lower floor's paste, puts into 100 ℃ of oven dry of baking oven, grinds 400 mesh sieves, obtains the nano-TiO that surface modification is crossed
2
Embodiment 3:
With 20g technical grade Nano graphite powder in the sodium hydroxide solution that joins 200ml mass percent concentration 30%, after soaking 12 hours under 50 ℃, remove by filter sodium hydroxide solution, Nano graphite powder after filtering is put into 110 ℃ of oven dry of baking oven, grind 400 mesh sieves, obtained the alkaline nano Graphite Powder 99.
Embodiment 4:
With 100g technical grade Nano graphite powder in the sodium hydroxide solution that joins 900ml mass percent concentration 10%, after soaking 24 hours under 60 ℃, remove by filter sodium hydroxide solution, Nano graphite powder after filtering is put into 110 ℃ of oven dry of baking oven, grind 400 mesh sieves, obtained the alkaline nano Graphite Powder 99.
Embodiment 5:
(1) gets the first grade hexanolactam of 500g and the nano-TiO that 2g crosses through surface modification
2The Nano graphite powder that (embodiment 1) and 2g cross through basic treatment (embodiment 3) mixes, join in the reactor, stirring also heats to 130 ℃, bleed with vacuum pump, making the reactor internal gas pressure is 100Pa, remove the moisture in the raw material, continue to stir the hexanolactam melted blend 40 minutes, obtain containing the hexanolactam melt of nano composite material;
(2) sodium hydrate solid with 1.5g joins step 1) in the hexanolactam melt that contains nano composite material that obtains, and maintenance reactor internal gas pressure is 100Pa, be warmed up to 145 ℃, continue to stir 30 minutes, basic catalyst is dissolved in the hexanolactam, and the moisture of reaction is removed, obtain the alkaline caprolactam melted blend;
(3) logical nitrogen is in reactor, until reactor pressure is elevated to normal atmosphere, under the violent stirring condition with the 3-isocyanic ester methylene-3 of 1.5g, 5,5-3-methyl cyclohexanol based isocyanate (IPDI) joins in the above-mentioned alkaline caprolactam melted blend, stir, be warming up to simultaneously 150 ℃, obtain pouring into a mould the hexanolactam nylon performed polymer of nylon;
(4) will pour into a mould with mould and be placed in the heating container, be preheating to 170 ℃ and constant temperature more than 10 minutes, hexanolactam nylon performed polymer is injected in the mold cavity by gravity flow or pressurization, the follow-up continuation of insurance temperature of close die 40 minutes, then naturally cool to room temperature, namely obtain self-lubricating high-strength pouring nylon parts.
The self-lubricating high-strength pouring nylon of present embodiment 5 preparations is compared with the common cast nylon that does not contain nano composite material, and the main raw performance data is as follows:
Material property |
Unit |
Common cast nylon |
This routine self-lubricating high-strength pouring nylon |
Density |
g/cm
3 |
1.15 |
1.16 |
Tensile strength |
MPa |
85 |
105 |
Elongation at break |
% |
40 |
30 |
Flexural strength |
MPa |
90 |
105 |
Ultimate compression strength |
MPa |
95 |
120 |
Shock strength (breach) |
KJ/m
2 |
6.0 |
7.0 |
Shao Shi D hardness |
|
80-85 |
85-90 |
Frictional coefficient |
μ |
0.4 |
0.11 |
Embodiment 6:
(1) gets the first grade hexanolactam of 500g and the nano-TiO that 10g crosses through surface modification
2The Nano graphite powder that (embodiment 1) and 10g cross through basic treatment (embodiment 3) mixes, join in the reactor, stirring also heats to 125 ℃, bleed with vacuum pump, making the reactor internal gas pressure is 80Pa, remove the moisture in the raw material, continue to stir the hexanolactam melted blend 30 minutes, obtain containing the hexanolactam melt of nano composite material;
(2) sodium hydrate solid with 3.5g joins step 1) in the hexanolactam melt that contains nano composite material that obtains, and maintenance reactor internal gas pressure is 80Pa, be warmed up to 150 ℃, continue to stir 40 minutes, basic catalyst is dissolved in the hexanolactam, and the moisture of reaction is removed, obtain the alkaline caprolactam melted blend;
(3) logical nitrogen is in reactor, until reactor pressure is elevated to normal atmosphere, under the violent stirring condition with the 3-isocyanic ester methylene-3 of 2.5g, 5,5-3-methyl cyclohexanol based isocyanate (IPDI) joins in the above-mentioned alkaline caprolactam melted blend, stir, be warming up to simultaneously 150 ℃, obtain pouring into a mould the hexanolactam nylon performed polymer of nylon;
(4) will pour into a mould with mould and be placed in the heating container, be preheating to 170 ℃ and constant temperature more than 15 minutes, hexanolactam nylon performed polymer is injected in the mold cavity by gravity flow or pressurization, the follow-up continuation of insurance temperature of close die 100 minutes, then naturally cool to room temperature, namely obtain self-lubricating high-strength pouring nylon parts.
Embodiment 7:
(1) gets the first grade hexanolactam of 1000g and the nano-TiO that 12g crosses through surface modification
2The Nano graphite powder that (embodiment 1) and 10g cross through basic treatment (embodiment 3) mixes, join in the reactor, stirring also heats to 130 ℃, bleed with vacuum pump, making the reactor internal gas pressure is 400Pa, remove the moisture in the raw material, continue to stir the hexanolactam melted blend 50 minutes, obtain containing the hexanolactam melt of nano composite material;
(2) sodium hydrate solid with 4g joins step 1) in the hexanolactam melt that contains nano composite material that obtains, and maintenance reactor internal gas pressure is 400Pa, be warmed up to 145 ℃, continue to stir 30 minutes, basic catalyst is dissolved in the hexanolactam, and the moisture of reaction is removed, obtain the alkaline caprolactam melted blend;
(3) logical nitrogen is in reactor, until reactor pressure is elevated to normal atmosphere, tolylene diisocyanate (TDI) with 6g under the violent stirring condition joins in the above-mentioned alkaline caprolactam melted blend, stir, be warming up to simultaneously 150 ℃, obtain pouring into a mould the hexanolactam nylon performed polymer of nylon;
(4) will pour into a mould with mould and be placed in the heating container, be preheating to 165 ℃ and constant temperature more than 25 minutes, hexanolactam nylon performed polymer is injected in the mold cavity by gravity flow or pressurization, the follow-up continuation of insurance temperature of close die 30 minutes, then naturally cool to room temperature, namely obtain self-lubricating high-strength pouring nylon parts.
Embodiment 8:
(1) gets the first grade hexanolactam of 500Kg and the nano-TiO that 8Kg crosses through surface modification
2The Nano graphite powder that (embodiment 2) and 8Kg cross through basic treatment (embodiment 4) mixes, join in the reactor, stirring also heats to 125 ℃, bleed with vacuum pump, making the reactor internal gas pressure is 80Pa, remove the moisture in the raw material, continue to stir the hexanolactam melted blend 50 minutes, obtain containing the hexanolactam melt of nano composite material;
(2) sodium hydrate solid with 4Kg joins step 1) in the hexanolactam melt that contains nano composite material that obtains, and maintenance reactor internal gas pressure is 80Pa, be warmed up to 145 ℃, continue to stir 30 minutes, basic catalyst is dissolved in the hexanolactam, and the moisture of reaction is removed, obtain the alkaline caprolactam melted blend;
(3) logical nitrogen is in reactor, until reactor pressure is elevated to normal atmosphere, under the violent stirring condition with the 3-isocyanic ester methylene-3 of 2.5Kg, 5,5-3-methyl cyclohexanol based isocyanate (IPDI) joins in the above-mentioned alkaline caprolactam melted blend, stir, be warming up to simultaneously 150 ℃, obtain pouring into a mould the hexanolactam nylon performed polymer of nylon;
(4) will pour into a mould with mould and be placed in the heating container, be preheating to 175 ℃ and constant temperature more than 30 minutes, hexanolactam nylon performed polymer is injected in the mold cavity by gravity flow or pressurization, the follow-up continuation of insurance temperature of close die 120 minutes, then naturally cool to room temperature, namely obtain self-lubricating high-strength pouring nylon parts.
Embodiment 9:
(1) gets the first grade hexanolactam of 100Kg and the nano-TiO that 1.4Kg crosses through surface modification
2The Nano graphite powder that (embodiment 2) and 1.5Kg cross through basic treatment (embodiment 4) mixes, join in the reactor, stirring also heats to 125 ℃, bleed with vacuum pump, making the reactor internal gas pressure is 80Pa, remove the moisture in the raw material, continue to stir the hexanolactam melted blend 60 minutes, obtain containing the hexanolactam melt of nano composite material;
(2) sodium hydrate solid with 0.25Kg joins step 1) in the hexanolactam melt that contains nano composite material that obtains, and maintenance reactor air pressure is 80Pa, be warmed up to 145 ℃, continue to stir 40 minutes, basic catalyst is dissolved in the hexanolactam, and the moisture of reaction is removed, obtain the alkaline caprolactam melted blend;
(3) logical nitrogen is in reactor, until reactor pressure is elevated to normal atmosphere, tolylene diisocyanate (TDI) with 0.3Kg under the violent stirring condition joins in the above-mentioned alkaline caprolactam melted blend, stir, be warming up to simultaneously below 150 ℃, obtain pouring into a mould the hexanolactam nylon performed polymer of nylon;
(4) will pour into a mould with mould and be placed in the heating container, and be preheating to 175 ℃ and constant temperature more than 30 minutes, hexanolactam nylon performed polymer is injected in the mold cavity by gravity flow or pressurization, the follow-up continuation of insurance temperature of close die 120 minutes, then naturally cool to room temperature, namely obtain self-lubricating high-strength pouring nylon parts.
The performance perameter of the self-lubricating high-strength pouring nylon parts of this law preparation is as follows:
Material property |
Unit |
The self-lubricating high-strength pouring nylon |
Density |
g/cm
3 |
1.15-1.21 |
Tensile strength |
MPa |
90-105 |
Elongation at break |
% |
25-30 |
Flexural strength |
MPa |
100-110 |
Ultimate compression strength |
MPa |
110-130 |
Shock strength (breach) |
KJ/m
2 |
>6.8 |
Shao Shi D hardness |
|
83-90 |
Frictional coefficient |
μ |
0.10-0.12 |