JPS5954880A - Steel pipe coated with resin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

The present invention relates to a resin-coated steel pipe that is easy to coat and particularly has excellent low-temperature impact resistance. In recent years, composites of polyolefins and metals (coating, lamination, etc.) have been used for purposes such as corrosion prevention 1)-1, improvement of surface functions such as decoration, prevention of environmental pollution such as sound insulation and vibration isolation, and energy saving by reducing waste. On the other hand, adhesive resins have been developed in which adhesive properties are imparted to polyolefins by modifying them with unsaturated carboxylic acids. This modified polyolefin is
It has a semi-permanent pot life and can be stored in the desired state such as powder, pellet, or film, allowing you to select the optimal shape for the bonding process.Also, since it is solvent-free, there are no problems caused by organic solvents. It is an excellent adhesive resin that can solve many of the problems found in conventional liquid adhesives, such as the fact that there are no adhesives. Such a modified polyolefin is used as a material for laminating a metal and a polyolefin therebetween, but in this case, the modified polyolefin and the polyolefin are usually polymers of the same type. Examples of such polyolefins and modified polyolefins include propylene polymers and ethylene polymers (low, medium, and
of high strength), ethylene vinegar/・it e-,・
・Basic mold & ni etc. □A6・ ,・ 11・
. Among them, propylene polymer has excellent rigidity, heat resistance, surface resistance, etc.1, but when applied to the recovery of steel pipes, it has poor impact resistance, especially at low temperatures. The reality is that the range of use for moxibustion is limited because there is not enough urine. The same applies to modified propylene polymers. The purpose of the present invention is to provide a propylene polymerized steel pipe having excellent impact resistance, particularly low-temperature impact resistance. When used in conjunction with the modified pro increase layer ``Tani Taiki'Jii'',...
,・：layer,″ □ ・□Seeing that this goal is achieved, I will put it out there and make a tower. ,,,,
,,5 That is, the present invention provides [(a) crystalline propylene polymer (
☆Contains 1 fat and optionally an olefin polymer of Lee et al., at least a part of which is graft copolymerized with an unsaturated carboxylic acid or its anhydride, and has a propylene content of 50 to 97% by weight・J and unsaturated carboxylic acid or its anhydride) 1', Bogaho α1-J1
(b) Crystalline propylene polymer resin and optionally ■ Others? Contains onilefin polymer 1, pro, pyrene, 6.5~9
9.5% by weight and melt flow
, lo5~10 y7: L' 0 minutes is a resin-coated pipe characterized by applying resin' on the surface of the steel pipe. Resin-treated steel pipes have sufficient resistance to impact, not only at temperatures above room temperature, but also at temperatures as low as -20°C and, in some cases, below -40°C.
There is a wide range of applications. The above wholesale Henmon resin used in the present invention is [Crystalline Block]
Robylene polymerization, polymerization, polymerization, and polymerization of other olefins, including at least one of these. Part of polymer 5 unsaturated, 〃, Report: I! Also. The anhydride is graft-polymerized, the dipropylene content is 50 to 97% by weight, preferably 55 to 95% by weight, particularly preferably 60 to 90% by weight, and the unsaturated carboxylic acid content is 50 to 97% by weight. Anhydride content is 0.0・″1~′10 by weight,
・A modified phase having a suitable size of 0.05 □ to 5*' weight, particularly preferably 1 digit of 0.1 to 3 ・weight □-1F). ``Crystalline polypropylene polymer resin'' is a homopolymer of propylene; the majority of the weight is propylene and other α-
Olelyzo←For example, ethylene, sheeten-1, input
7
1 is combined with balding, V-sulfur, and silanization, □, which has undergone modification such as oxidation, silanization, etc., and is a black-heading resin □.・ １・ ・−′□″Ku□・Mata-
``Other Ti/Fin polymers that may be added/added if necessary'', for example, □bait/V-shield.

[Pute Sea 1
, ・A monopolymer of α-olepiin other than propylene resin such as hexene-1,4-methylbezotycin 1: A blog with α-olepiin, a monopolymer of α-olepiin other than propylene, propylene, etc. Or a random copolymer; other than the majority of the weight of brobylets: a multi-component block of α-□olefin (single type or multiple types may be used)' and propylene, or a random copolymer resin or rubber. , preferred examples include evaporated polyethylene, ethylene-
(vinyl acetate) copolymer, ethylene-propylene propylene or random copolymer, containing ethylene-propylene-butene-1
Brotun□ or random copolymer, pressure ethylene rubber □ Robylene group type combination 'rubber □ (E"pm) □X' engineering ≠ Ren]
Examples include propylene-diele copolymer rubber (EP'D''M). , maleic acid □, itaconic acid, hymic acid □ Ibakowara □ anhydride □ etc. □ Among them, □ acrylic acid □ and male diic anhydride □ are preferred □, especially anhydride-rein i. Yo□ii= ・
□ −・・
□Graft copolymerization of unsaturated carboxylic acids or their anhydrides can be carried out using methods such as irradiation with ionizing radiation, ultraviolet rays, etc., methods using radical generators, and methods using oxygen, budsin, □′m1, etc. 7-1 Solution state, slurry IJ-state, molten state, etc. using conventional methods (performed from 't') First, among these methods, a method in which the graft reaction is carried out using a radical initiator in a solution state in an organic solvent or in a molten state in a mixer is particularly preferred. After the reaction, if necessary, an unreacted removal step, a drying step, etc. may be performed. It should be understood that there is (1) A-I) I) (2) A,, -PI) + PP'! h- and 7/
or PO(3)A-(1)P-1-PO) (4)A-(PP 10PO) + PP and/or p. (5) A-i) 0 + PP (f;j A -PP 10A -PO (7) A -J:'P' -A -1'o + PP and/or PO where PP is crystalline propylene Polymer resins can be used to refer to other olefin polymers, such as A
-PI) is a mixture of I) P with unsaturated carboxylic acid or its anhydride, and A-(PP+PO) is a mixture of PP and PO. The kraft copolymerized anhydride/') is shown in each □. Modification (■ Preferred embodiments of the fat include the following. (2) Co-i1r combination based on the modified resin of (1) above,
or diluted with polypropylene. (3) Polypropylene graft-modified with an unsaturated carboxylic acid or anhydride. (4) The modified resin of (3) above is appropriately diluted with polyethylene, polypropylene, propylene-α-oj/fin (excluding propylene) block, randano, or copolymer. (5) A product obtained by adding ethylene-propylene copolymer rubber (EPM, EPDM) to the modified resins of (1) to (4) above. ? If the propylene content of the &+'1 crumbled fat is less than the above range, the adhesion to the steel pipe at high temperatures will not be sufficient, and the adhesion to the resin described in (b) below will also be insufficient. When the layer is overturned, the low temperature (impact resistance deteriorates) is not very large. If there is too little, the adhesive force will not be sufficient,
Excessive reduction in size will have a negative effect on mechanical strength and appearance [7] This is not desirable. From the viewpoint of moldability, melt flow rate (t1MI'H) of 0.1 to 109/10 minutes is especially desirable for women. In this case, polymers, inorganic fillers, stabilizers, lubricants, antistatic agents, antiblocking agents, etc. may be added as other components within the range that does not impede the effects of the invention. There are styrene polymers, polyamide polymers, polynisder polymers, etc., and these can be used singly or in combination.Inorganic fillers include calcium carbonate, talc, titanium oxide, Clay, Anomina, Serai l-1 Ryo Sbest, barium sulfate, stone, etc. are also used.Next, the resin (t; 1, "crystalline propylene polymer Contains other olefin polymers depending on the resin and μmole, and contains propylene [(F is 65 to 99
．． 5-fold ijf, preferably 75 to 97 small ifl and MFR of 0.05 to 109/1. (1 minute, preferably from 0.1 to 5y/1o minutes.
However, each of the modified resins disclosed in (a) above can be applied by cutting them, but among them, crystalline propylene-α-silica-fin block copolymer, especially crystalline propylene-2,11 / Nbu! ] Tsuku copolymers are preferred in view of the balance between mechanical strength and the effects of the present invention. These can also be selected from commercially available products. When the propylene content of the resin (b) is less than the above range by 1, the mechanical strength [81] is insufficient, especially at high temperatures, and if there are too many cavities, the low-temperature impact resistance deteriorates. If the MFR is high, the creep resistance is poor, and when extrusion coating is performed, the melt tension is low. The load on the tip tube and motor increases, causing the push seat to become heavier. When it comes out, the surface looks like sharkskin or melt fracture, and is said to be in an unfavorable state. This (b) resin is also commonly used! colorant,
Inorganic filler, stabilizer, purple FW silencing agent 1. ．． Additives such as lubricants and other polymers can be added within a range that does not impede the development effect. The resin-coated steel pipe of the present invention, the curvature and gender of the above (a)
The resin described in (b) above is coated on the steel pipe via Jll\j. Steel pipes are subjected to various surface treatments such as chromate treatment, zinc phosphate treatment, etc., or sandblasting, clear lard, and shock treatment before being subjected to drying and repair. Pluses such as Do Blast and Sour Fu Jing! - or it is preferable to use one that has been subjected to surface contamination removal treatment. In addition, to improve adhesion and durability when the preheating temperature of the steel pipe is low during resin coating, it is possible to apply a brimer such as a hardening epoxy resin to the surface of the pipe before applying the modified resin. Painting d! f@ , B 6 ”''
□ As the brimer, thermosetting epoxy resin, urethane resin, unsaturated polyester resin, etc. are used, but q-
Z! Alternatively, it is a thermosetting, a, or arsenic epoxy resin. The thermosetting epoxy resin refers to an epoxy resin mixed with a curing agent. Furthermore, it is also possible to combine viscosity II regulators, melting agents, accelerators, reactive diluents, extenders, fillers, carbon, etc., which are usually added to the epoxy resin. As a method for coating the steel pipe with resin, an appropriate number of known methods may be used, such as extrusion: '-f4yf method, powder coating method, etc. Plastic: If Fuma is not used, JIS-K 7207 (18, 5K) is a modified resin used to stiffen the surface of the steel pipe.
It is preferable to heat the material to a temperature equal to or higher than the deflection temperature measured by yf/t$ load), and then fuse the negative resin. Furthermore, when using a brimer, apply a brimer such as thermosetting epoxy resin to the surface of the steel pipe in advance; 2. After semi-hardening or completely curing, the modified resin is fused. is preferred. . In particular, when using a brimer, the temperature in the preheating process of the steel wire can be lowered. 9, it is possible to shorten heating and cooling times and thereby reduce production costs. . Next, an example of decoration will be shown, and the evaluation method in the example was as follows. (1) MFR: JIS-Ni 721 Hill Pass* Case 14
(2) Molding sag: The resin film extruded from the die during molding grows sag due to its own weight, causing uneven thickness before contacting the door pipe, which can be improved by controlling the sag, tip, and tube. Summer water, sometimes molded * (×), outside was rated good (○,). ,. (3) Molding heat generation/appearance: generation of heat inside the machine during molding (7
, the temperature may rise to over 280 degrees Celsius, or the school may become open to the public at the exit of the chair, resulting in a disastrous situation! occurred. S (X),
The outside was rated as good (○). ,,. (4) Low-temperature impact resistance: Based on ASTM-G14. The temperature control section uses Doori-Eta and Nord refrigerants.
The height is 40α at -45℃ with a hammer load of 52Kg.
Destruction when you lower your buttocks? Detect the presence with a pinhole tester, and mark the presence as defective (×)1. (5) High temperature needle penetration degree: according to DIN30670:
The condition of the τ needle is 1.0 mm, and the depth is 0.4 tm or less as good (p), and the outside as poor. It was rated as good (x) and one of the best results. , (blank space below) □ Example〈Variation of (a) above +'t: 4y'i, J fat〉M ii
' [j o. 8y/lo polypropylene 5
002 and 5)<rWater mal/inl'195Of and chlorobenzene 104 were placed in a 20 t polymerization tank, and heated to 120°C while stirring.
After cooling to 5°C, benzoyl peroxide 402 dissolved in 25Qm/' of chlorobenzene was added dropwise using a dropping funnel over a period of 1 hour, and after the addition, polymerization was completed at 105°C for another 4 hours. After the reaction was completed, the mixture was cooled to about 60° C., the reaction solution was added to a large HL of acetone, and the precipitated polymer was washed door to door at t7. b1) Wash the resulting polymer repeatedly with large amounts of acetone,
A maleic anhydride modified polypropylene was obtained. The maleic anhydride content in the resulting single layer is determined by the infrared absorption
As measured by 17 spectral analysis, 6fold [i:%
Met. 17 like this? ! The obtained modified polymer and various propylene polymers were mixed in a weight ratio of 5:95. At this time, 2.6-di-t-butyl-p-cresol was added as an oxidation agent (+7+1.0.+) to the blend.
0.05% by weight of calcium stearate was added as a neutralizing agent. These were mixed using a Henshuhl mixer. This mixture was extruded into strands using an extruder set at 230°C, and pelletized using a pelletizer. The obtained modified resins were of the following 3fiI type, and the maleic anhydride content was 4%, respectively. A: Maleic anhydride-modified polypropylene is mixed with the same polypropylene as this base polymer (MF 1.to, s
Resin B: maleic anhydride-modified polypropylene diluted with MFRo,
Resin C diluted with a propylene-ethylene block copolymer powder having an ethylene content of 1511'j% for 89710 min: 100 ja parts of the above resin 13 and a Mooney viscosity of 10
0°C (ML) is 105, propylene content is 431, 'j ("C%, ethylidene norbornene content is F
a Resin kneaded by kneading the 15% ethylene/propylene/diene based composite rubber in an extruder (111 kg) J]'r's> Table 1 shows the production of resins such as Meit paulownia. The polymerization method used was Senjo's j-refin polymerization method, but for example,
Propylene-ethylene block copolymer (b) in Table 1 was produced by the following method. Contents Kft120t;A-) 40t1 heptane in crepe 30? and diethylbluminium chloride 60f were charged. pp In the 1-stage polymerization, propylene was introduced into the autoclave at 60° C. so that the internal use was 4 kg/tric, and polymerization was carried out for about 3.5 hours. During this time, the gas phase hydrogen concentration was maintained at 5% by volume. ]' After the completion of the first stage polymerization, the remaining propylene was purged with K 1.5 Kg/a41, and a mixture of propylene and ethylone with an ethylene monomer ratio of 60 mol% was added to the liquid. It was introduced from the phase for 2.5 hours at 3.4 Kg/hr. A mixture of butanol and heptane was added to the resulting polymerization slurry to deactivate the catalyst, then extracted with water to separate into two layers, and the oil phase was centrifuged to separate the polymer. 20 kg of powder was obtained. To this powder was added 0.1% by weight of 2,6-di-t-glysol-p-cresol and calcium stearate.
% by weight was added and granulated using an extruder at 230°C. The MFR of this pellet was x, 2y/1o. The other resins shown in Table 1 were obtained by manipulating the cumulative water concentration in the first stage polymerization and the ethylene content in the second stage polymerization in the above polymerization process. (from -1 margin) 1st. table ,. (Note) *: Only in the table, ML1+4 is 75% by weight in 100 parts by weight of the polymer having the MFR and propylene content.
, a blend of 10 parts by weight of an ethylene-propylene copolymer rubber having an ethylene content of 28% by weight. <Coating of Steel Pipe> The outer surface of a 20A steel pipe (outer diameter 27.2 van) was sandblasted and preheated to 160°C. , . Stolen number 1. The above modified resin (a) and the above resin (b) were each plasticized in different 49-diameter extruders to produce amorphous material. The preheated steel pipe was extruded from a lower coextrusion round die at 230°C into a circular sheet (wall thickness ratio: former: latter = 1:6) with the resin on the inside. After coating with resin, it was introduced into a water tank and cooled with water to obtain a coated steel pipe with a resin layer thickness of 2.5 mm. This coating 1#1! Leave it at room temperature for more than a day to shape, (
I used it as a test tube. The results of the evaluation are shown in Table 2. (Margin below)

Claims (1)

[Claims] (a) Contains a crystalline propylene polymer resin and optionally other olefin polymer, at least a part of which is graft-copolymerized with an unsaturated carboxylic acid or its anhydride, and a globylene-containing FQ Suke S 50~
(b) Crystalline propylene polymer resin and other olefin polymers by aggregation through equipment-modified resin with anhydride content of 0.01 to 10% by weight of unsaturated carponide Contains, propylene content is 65
~99.5% heavy chain and melt flow rate of 0.05
1. A resin-coated steel pipe, characterized in that the surface of the steel pipe is coated with a resin having a heat resistance of ~10 f/10 min.