CN109679237B - Resin molded article, molding method thereof, cable and manufacturing method thereof - Google Patents
Resin molded article, molding method thereof, cable and manufacturing method thereof Download PDFInfo
- Publication number
- CN109679237B CN109679237B CN201810717273.6A CN201810717273A CN109679237B CN 109679237 B CN109679237 B CN 109679237B CN 201810717273 A CN201810717273 A CN 201810717273A CN 109679237 B CN109679237 B CN 109679237B
- Authority
- CN
- China
- Prior art keywords
- extruder
- resin molded
- crosslinking
- molded article
- organotin
- 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.)
- Active
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
- C08K13/00—Use of mixtures of ingredients not covered by one single of the preceding main groups, each of these compounds being essential
- C08K13/02—Organic and inorganic ingredients
-
- 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
- C08K3/02—Elements
- C08K3/04—Carbon
-
- 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
- C08K5/04—Oxygen-containing compounds
- C08K5/14—Peroxides
-
- 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
- C08K5/54—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
- C08K5/00—Use of organic ingredients
- C08K5/56—Organo-metallic compounds, i.e. organic compounds containing a metal-to-carbon bond
- C08K5/57—Organo-tin compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/34—Electrical apparatus, e.g. sparking plugs or parts thereof
- B29L2031/3462—Cables
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2203/00—Applications
- C08L2203/20—Applications use in electrical or conductive gadgets
- C08L2203/202—Applications use in electrical or conductive gadgets use in electrical wires or wirecoating
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2312/00—Crosslinking
- C08L2312/08—Crosslinking by silane
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Organic Insulating Materials (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
- Processes Specially Adapted For Manufacturing Cables (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Insulated Conductors (AREA)
Abstract
The invention provides a resin molded article, a molding method thereof, and a cable and a manufacturing method thereof, wherein the resin molded article can inhibit bad appearance 'particles or roughness' caused by early crosslinking when the amount of an organotin crosslinking catalyst is increased to increase the crosslinking speed and the Sn/Si is more than 5%. When the organotin-based crosslinking catalyst is fed to the extruder side, the occurrence of "particles" which are poor in appearance due to insufficient kneading can be suppressed. The resin molded article of the present invention is characterized by containing a silane-crosslinked chlorine-based polymer, by containing 5% or more of Sn from an organotin-based crosslinking catalyst relative to Si from a silane compound, and by having a smooth surface.
Description
Technical Field
The present invention relates to a resin molded article, a molding method thereof, a cable, and a manufacturing method thereof.
Background
As a molding method of the resin molded product, there is, for example, a molding method of a sheath of a cable.
The cable sheath molding method comprises mixing particles of a silane crosslinkable composition comprising a matrix polymer comprising chlorinated polyethylene as a chlorine-based polymer and a silane compound, with master batch particles comprising the matrix polymer comprising chlorinated polyethylene and an organotin crosslinking catalyst to prepare a silane crosslinkable composition, extruding the prepared silane crosslinkable composition onto an insulated wire by an extruder to form a sheath, and subjecting the sheath to a silane crosslinking treatment to mold a silane crosslinked chlorinated polyethylene sheath.
According to this cable, excellent results can be obtained in evaluation of the presence or absence of bleeding, gel fraction (%) after crosslinking, tensile elongation (%), and the like (table 1 of patent document 1).
Prior art literature
Patent literature
Patent document 1: japanese patent laid-open No. 2017-27887
Disclosure of Invention
Problems to be solved by the invention
However, according to this method for molding a sheath of a cable, since the silane crosslinkable composition containing the organotin-based crosslinking catalyst is heated throughout the period from the time when the prepared silane crosslinkable composition is supplied from the hopper of the extruder to the time when the composition is discharged from the die, if the crosslinking rate is to be increased, the early crosslinking (also referred to as "scorching" but hereinafter not referred to as "scorching" but as "early crosslinking") occurs if the Sn/Si ratio of Si derived from the silane compound to Sn derived from the organotin-based crosslinking catalyst is 5% or more, and there is a possibility that "particles or roughness" causing a poor appearance of the sheath will be molded on the sheath surface.
In order to suppress the poor appearance of the sheath, it has been studied that the organotin-based crosslinking catalyst is not supplied from a hopper of the extruder but is supplied from a cylinder at a position intermediate between the hopper and the die (hereinafter referred to as "side feed"), and if the distance between the side position of the cylinder and the die becomes short, insufficient kneading of the silane-crosslinkable composition and the organotin-based crosslinking catalyst occurs, and there is a possibility that "particles" may be generated on the surface of the sheath.
Accordingly, an object of the present invention is to provide a resin molded article capable of suppressing appearance defects of "particles or roughness" due to early crosslinking when the amount of an organotin-based crosslinking catalyst is increased to increase the crosslinking rate and the Sn/Si is 5% or more, a molding method thereof, and a cable and a manufacturing method thereof.
Another object of the present invention is to provide a resin molded article capable of suppressing appearance defects caused by "particles" due to insufficient kneading when the organotin-based crosslinking catalyst is fed to the extruder side, a molding method thereof, and a cable and a manufacturing method thereof.
In the present invention, the above "particles" and "roughness" are defined as follows.
"particles": bulge (bump) with a size of about 1mm and a height of about 0.1-0.5 mm
"roughness": a large amount of particles appeared, and surface irregularities (surface roughness Ra (arithmetic average roughness) =about 0.5 to 1 mm)
In addition, in the present invention, "surface smoothness" of the resin molded article or the cable sheath is defined as not having the above-mentioned "particles" or "roughness".
Means for solving the problems
In the present invention, it is considered that if the crosslinking catalyst is side-fed in the middle of the extruder, the heat applied in the extruder can be minimized, and early crosslinking can be suppressed. In particular with a view to t at each temperature in the rheological torque curve as target for the onset of crosslinking 10 The scorch time is considered to be capable of suppressing early crosslinking if the heat applied in the extruder is set to a thermal process equal to or less than the scorch time.
Therefore, attempts have been made to reduce the thermal process by side-feeding an organotin-based catalyst liquid as a silane crosslinking catalyst in the middle of an extruder.
On the other hand, if side feeding is performed, the thermal process can be reduced, but there is a possibility that dispersion and kneading of the catalytic element (Sn) are poor. In order to achieve good dispersive mixing, the mixing time in the extruder must be increased.
In the present invention, therefore, the silane crosslinking catalyst is fed to the side of the kneading time required for uniformly dispersing and kneading the silane crosslinking catalyst, and the kneading time is not shorter than the heating time for early crosslinking.
Specifically, the term "kneading time required for uniformly dispersing and kneading the silane crosslinking catalyst" is set so that the total shear distortion epsilon acting in an extruder equipped with a single screw is 400 or more. Specifically, the "position less than the heating time at which early crosslinking occurs" is a position at which the crosslinking progress of the extruder outlet is 10% or less.
In order to achieve the above object, the present invention provides the following resin molded article and molding method thereof, and a cable and manufacturing method thereof.
[1] A resin molded article comprising a silane-crosslinked chlorine-based polymer, wherein the mass ratio of Sn from an organotin-based crosslinking catalyst to Si from a silane compound is 5% or more, and the surface is smooth.
[2] A cable comprising a core covered with a sheath, wherein the sheath is composed of the resin molded article of [1 ].
[3] A method for molding a resin molded article, comprising a step of supplying a silane-crosslinkable resin composition containing a silane compound, which is a matrix polymer comprising a chlorine-based polymer, into an extruder cylinder from an upstream position of the cylinder, a step of supplying an organotin-based crosslinking catalyst into the cylinder from a downstream position downstream of the upstream position of the extruder cylinder, and a step of molding a resin molded article by extruding the kneaded mixture from a die of the extruder while preparing a kneaded mixture of the silane-crosslinkable resin composition and the organotin-based crosslinking catalyst; in the step of supplying the organotin-based crosslinking catalyst, the organotin-based crosslinking catalyst is supplied by setting a mass ratio of Sn contained in the organotin-based crosslinking catalyst to Si derived from the silane compound to 5% or more; further, by preventing the early crosslinking of the kneaded material, the 1 st appearance defect "particles" or "roughness" is not generated on the surface of the resin molded product, and the downstream position is set to a region of the extruder cylinder where the 1 st appearance defect is not generated.
[4] The method of molding a resin molded article according to [3], wherein in the step of supplying the organotin-based crosslinking catalyst, the downstream position is set between a downstream end of a region where the 2 nd appearance defect does not occur and an upstream end of a region where the 1 st appearance defect does not occur by preventing insufficient kneading of the kneaded article and preventing occurrence of the 2 nd appearance defect "particles" on the surface of the resin molded article.
[5] A method for molding a resin molded article which is a resin molded article obtained by crosslinking silane and which contains a chlorine-based polymer complex containing a silane compound and an organotin-based crosslinking catalyst, wherein the mass ratio of Sn (Sn/Si) to Si in the resin molded article is 5% or more and less than 15%; the organotin-based crosslinking catalyst is fed to a position where the total shear distortion epsilon acting in an extruder having a single screw is 400 or more and the crosslinking progress at the outlet of the extruder is 10% or less.
[6] A method for producing a cable, comprising the step of coating a sheath on a cable core by the method for molding a resin molded article according to any one of [3] to [5 ].
ADVANTAGEOUS EFFECTS OF INVENTION
According to the present invention, it is possible to provide a resin molded article capable of suppressing appearance defects caused by "particles or roughness" due to early crosslinking when the amount of an organotin-based crosslinking catalyst is increased to 5% or more in order to increase the crosslinking speed, a molding method thereof, and a cable and a manufacturing method thereof.
Further, according to the present invention, there can be provided a resin molded article capable of suppressing appearance defects caused by "particles" due to insufficient kneading when the organotin-based crosslinking catalyst is fed to the extruder side, a molding method thereof, and a cable and a manufacturing method thereof.
Drawings
Fig. 1 is a schematic view for explaining steps of a method for manufacturing a cable according to an embodiment of the present invention.
FIG. 2 shows the amounts of catalyst (Sn/Si ratio), the scorch time T at the temperature T of the rheometer 10 A graph of the measurement results of (a).
FIG. 3 is a graph showing the results of deriving the crosslinking speed k (T) at each temperature from the rheometer measurement results based on Arrhenius' law.
Fig. 4 is a graph showing the result of deriving the material temperature rise function T (T) by particle simulation (particles) in the case of using the extruder having four positions (a) to (D) at the side feed position.
FIG. 5 shows the flow chart from FIG. 3And the results and numbers of FIG. 4 [1]]The residence time t in the extruder and the crosslinking progress were determined by feeding the catalyst side at the positions (A) to (D)Is a graph of one example of the relationship of (a).
FIG. 6 shows the residence time t in the extruder and the final crosslinking scheduleIs a graph of the relationship of (1).
Fig. 7 is a graph showing the relationship between residence time t in the extruder and shear rate γ in the case of using screws α and β.
Fig. 8 is a graph showing test results of examples and comparative examples.
Symbol description
10: a cable; 11: a cable core; 12: a silane crosslinked sheath; 100: an extruder; 1: extruding a screw; 2: a material inlet; 3 to 5: a catalyst pressure inlet; 6: a pump; 7: a catalyst container; 20: a chlorine-based polymer material; 21: and (3) a catalytic liquid.
Detailed Description
[ resin molded article ]
The resin molded article according to the embodiment of the present invention is characterized by containing a silane-crosslinked chlorine-based polymer, having a content of Sn from an organotin-based crosslinking catalyst of 5% by mass or more relative to Si from a silane compound, and having a smooth surface. Surface smoothing refers to a state where the surface is free of "particles", "roughness". Preferably, the surface roughness Ra (arithmetic average roughness) =0.1 mm or less.
The resin molded article according to the embodiment of the present invention is a silane-crosslinked resin molded article containing a chlorine-based polymer composite material containing a silane compound and an organotin-based crosslinking catalyst, and the mass ratio of Sn element (Sn/Si) to Si element in the resin molded article is preferably 5% or more and less than 15%.
The chlorine-based polymer composite material used in the embodiment of the present invention is a composite material based on a chlorine-based polymer, and contains a silane compound and an organotin-based crosslinking catalyst.
Examples of the chlorine-based polymer include Chlorinated Polyethylene (CPE), chloroprene Rubber (CR), polyvinyl chloride (PVC), and a vinyl chloride-vinyl acetate copolymer.
As the silane compound, for example, methacrylic silanes such as 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl triethoxysilane, 3-methacryloxypropyl methyl dimethoxy silane, 3-methacryloxypropyl methyl diethoxy silane, etc. can be used.
The amount of the silane compound to be blended in the chlorine-based polymer may be appropriately changed depending on the degree of crosslinking of the final molded article (e.g., cable jacket) or the reaction conditions (e.g., temperature, time, etc.) at the time of crosslinking. Specifically, the amount of the silane compound to be blended is preferably 0.1 part by mass or more and 10 parts by mass or less, more preferably 1 part by mass or more and 6 parts by mass or less, relative to 100 parts by mass of the chlorine-based polymer.
The organotin-based crosslinking catalyst is a silanol-based condensation catalyst that promotes silane crosslinking. Examples of the organotin-based crosslinking catalyst include dioctyltin dineodecanoate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dioctanoate, stannous acetate and stannous octoate.
The amount of the organotin-based crosslinking catalyst blended in the chlorine-based polymer is such that the content ratio (Sn/Si) of Sn element (derived from the organotin-based crosslinking catalyst) to Si element (derived from the silane compound) in the resin molded product is 5% or more. The upper limit is preferably less than 15%. In the present invention, even if the concentration of the organotin-based crosslinking catalyst is high (the blending amount is increased more than usual) as described above in order to increase the crosslinking speed, an insulated cable having a good appearance can be obtained.
In addition to the silane compound and the organotin-based crosslinking catalyst, the chlorine-based polymer blend material contains a peroxide. As the peroxide, for example, an organic peroxide can be used, and specifically dicumyl peroxide, 1-bis (t-butylperoxy) cyclohexane, t-butylperoxyisopropyl carbonate, t-amyl peroxyisopropyl carbonate, 2, 5-dimethyl-2, 5-bis (t-butylperoxy) hexane, di-t-butyl peroxide, di-t-amyl peroxide, 1-bis (t-amyl peroxy) cyclohexane, t-butyl peroxy 2-ethylhexyl carbonate, and the like can be used. The number of these may be 1 alone or 2 or more.
The amount of the peroxide to be blended in the chlorine-based polymer may be appropriately changed depending on the amount of the silane compound to be blended, and is preferably 0.03 parts by mass or more and 3.0 parts by mass or less relative to 100 parts by mass of the chlorine-based polymer.
The chlorine-containing polymer blend may further contain plasticizers, antioxidants (including anti-aging agents), fillers such as carbon black, flame retardants, lubricants, copper discoloration inhibitors, crosslinking aids, stabilizers, and the like. The blending amount of these may be appropriately changed according to the use of the resin molded product.
[ method for molding resin molded article ]
The resin molded product according to the embodiment of the present invention can be obtained by, for example, the following molding method.
The method for molding a resin molded article according to an embodiment of the present invention comprises a step of supplying a silane-crosslinkable resin composition containing a silane compound, which is a matrix polymer of a chlorine-based polymer, into an extruder cylinder from an upstream position of the cylinder, a step of supplying an organotin-based crosslinking catalyst into the cylinder from a downstream position downstream of the upstream position of the extruder cylinder, and a step of molding a resin molded article by extruding the kneaded mixture from a die of the extruder while preparing the silane-crosslinkable resin composition and the organotin-based crosslinking catalyst into a kneaded article; in the step of supplying the organotin-based crosslinking catalyst, the organotin-based crosslinking catalyst is supplied by setting a mass ratio of Sn contained in the organotin-based crosslinking catalyst to Si derived from the silane compound to 5% or more; further, by preventing the early crosslinking of the kneaded material without occurrence of "particles" or "roughness" of the 1 st appearance defect on the surface of the resin molded product, the downstream position is set to a region of the extruder cylinder where the 1 st appearance defect is not generated.
In the molding method of the resin molded product according to another embodiment of the present invention, in the step of supplying the organotin-based crosslinking catalyst, by preventing the insufficient kneading of the kneaded material from occurring "particles" of the No. 2 poor appearance on the surface of the resin molded product, the downstream position is set between the downstream end of the region where the No. 2 poor appearance does not occur and the upstream end of the region where the No. 1 poor appearance does not occur.
In the method for molding a resin molded article according to the embodiment of the present invention, the organotin-based crosslinking catalyst is preferably fed to a position where the total shear distortion epsilon acting in an extruder having a single screw is 400 or more and the crosslinking progress at the outlet of the extruder is 10% or less.
By adjusting the groove depth of the single screw, the length ratio of the supply unit/compression unit/metering unit, and the side feed position of the organotin-based crosslinking catalyst, the total shear distortion ε can be 400 or more and the crosslinking progress at the extruder outlet can be 10% or less. The crosslinking progress at the outlet of the extruder is preferably 9.5% or less.
[ Cable and method for manufacturing the same ]
Fig. 1 is a schematic view for explaining steps of a method for manufacturing a cable according to an embodiment of the present invention. An embodiment of the present invention will be described below with reference to fig. 1.
In the cable 10 according to the embodiment of the present invention, the sheath 12 is formed of the resin molded product according to the embodiment of the present invention in the cable in which the cable core 11 is covered with the silane crosslinked sheath 12.
Examples of the cable core 11 include an individual conductor, an insulated wire having an insulator such as ethylene propylene rubber coated around the conductor, and a twisted core having a plurality of insulated wires twisted.
The material of the conductor is not particularly limited, and known materials can be used. For example, copper wire plated with tin, or the like is used. The number of conductors is not limited to 1, and may be a stranded wire in which a plurality of bare wires are stranded. The material of the insulator is not particularly limited, and may be formed using a known material.
The sheath 12 may be molded by extrusion molding using the resin molded product according to the embodiment of the present invention.
The method for manufacturing the cable 10 according to the embodiment of the present invention is to coat and mold the sheath 12 formed of the resin molded product on the cable core 11 by the molding method of the resin molded product according to the embodiment of the present invention. The jacket 12 is then exposed to an environment, such as 80 degrees celsius, 90% relative humidity, and reacted with moisture, thereby silane crosslinking the jacket 12.
The extruder 100 for extrusion molding preferably uses an extruder having a ratio L/D of the length L to the diameter D of the screw of about 15 to 30.
At the base of the extruder 100, a chlorine-containing polymer material 20 is fed through a material feed port 2, and an organotin catalyst solution 21 (stock solution) for silane crosslinking is fed from the middle of the extruder 100 through a pipe connecting the catalyst container 7 into which the catalyst solution 21 is fed and the catalyst feed port 3 by a pump 6 connected to the pipe.
The silane compound is kneaded in advance into the chlorine-based polymer, and is added as a liquid from the material inlet 2 and fed to the extruder 100 at the middle side thereof. When the silane compound is fed in the side direction, the silane compound is added to the side closer to the screw root than the side of the organotin catalyst liquid 21.
The present invention is characterized in that an organotin catalyst is fed and extruded at a position side of "capable of suppressing early crosslinking" and "capable of uniformly dispersing and kneading".
Early crosslinking is intimately associated with crosslinking.
In general, the degree of crosslinking is determined from a torque curve in a rheometer specified in JIS K6300-2.
The time required to reach 90% of the maximum torque τmax from the minimum torque τmin is taken as the scorch time t 90 As a target of the crosslinking progress. Scorch time t 90 According to the set temperature of the rheometer (about 150 ℃ C. To the upper limit180 ℃ is about 10 to 100 minutes. The higher the temperature, t 90 The smaller the value of (2).
On the other hand, in the case of an extruder, crosslinking is easily performed even at a temperature lower than that of a rheometer (about 90 to 150 ℃) by applying high shear with a screw. Thus, the crosslinking is carried out not after extrusion but in an extruder, and premature crosslinking occurs.
Early crosslinking is not only affected by temperature, but also occurs easily when the amount of crosslinking catalyst is increased.
In order to increase the crosslinking rate of the crosslinking (post-crosslinking) after extrusion, it is preferable to increase the amount of the crosslinking catalyst, but in the conventional art, the limit is extrusion under the condition that the mass ratio of Sn element to Si element (Sn/Si) is less than 5% in relation to the occurrence of premature crosslinking in the extruder, which is offset (Trade-off).
Thus, in the present invention, the torque curve of the rheometer is of interest in order to inhibit premature crosslinking. Specifically, the time before the initiation of crosslinking is taken as the scorch time t 10 (time required from τmin to reach 10% of τmax) as a function of the Arrhenius law and the temperature rise of the material in the extruder, as a function of the time to pass through each location in the extruderAnd is functionalized (the following expression [1]])。
[ number 1]
Here, t is the time (seconds) for passing through each position in the extruder when the time for feeding the material is set to 0 seconds; t (T) is the material temperature (K) at time T (sec); k (T)) is the crosslinking reaction rate at a material temperature T (T) (K) based on the arrhenius law;is the crosslinking progress (%).
For suppressing the early crosslinking, feeding at a position near the front end side of the extruder is preferable, but on the other hand, it is impossible to uniformly knead and disperse.
Whether or not the kneading is uniformly dispersed can be determined by the total shear distortion amount epsilon (expression [2] below).
[ number 2]
Here, γ (t) is the shear rate (seconds) at t (seconds) after being fed into the extruder －1 )，t in Time (seconds) to pass the location of side feed, t out The time (seconds) for passing the front end of the screw.
If the drawing is made such that the horizontal axis is set to the time (seconds) of passing through the extruder and the vertical axis is set to the shear rate (seconds) of each time －1 ) The equation [2]]Can be represented as the area of the graph.
In this embodiment, the position where early crosslinking can be suppressed (the catalyst press-in port 4 at the screw root) is specified by the following 1..about.5. And the position where kneading can be uniformly dispersed (the catalyst press-in port 5 at the screw tip) is specified by the following 6..about.7.
1. Sample piece with catalyst quantity changing relative to silane
2. Scorch time T determined based on changing the temperature T of the rheometer 10 The crosslinking reaction rate k (T) is derived from Arrhenius' law
3. Next, the crosslinking reaction rate k (T (T)) at each position in the extruder was derived using the rheometer temperature T as the material temperature T (T) in the extruder
4. Adapted to the above-mentioned formula [1]]Deriving the crosslinking progress at each position in the extruder
5. The extrusion experiment was performed by changing the amount of catalyst and the feeding position of the catalyst side. Deriving the crosslinking progress at the time of early crosslinking
6. Based on the above equation [2], the feed position and the total shear distortion amount on each side are derived
7. Observing the cross section of the extrusion molding, and deriving the threshold value of the total shearing deformation epsilon of uniformly dispersed Sn
When the material is fed from the catalyst inlet 4 to the catalyst inlet 5, a good extrusion molded product having a mass ratio of Sn element to Si element (Sn/Si) of 5% or more and less than 15% can be provided.
The present invention is applicable to a method in which a chlorine-based polymer is charged as a main material and an organotin catalyst for silane crosslinking is charged as a sub-material in the middle of an extruder, as long as it is a compounding material (compounding material for a chemical reaction caused by heat in an extruder) in which early crosslinking due to a chemical reaction in an extruder is problematic.
In addition, in the case where a material is fed from the base of an extrusion screw in the related art, since the speed is limited by the passage time in the extruder, extrusion cannot be performed by blending a material having a high chemical reaction rate. Therefore, it is necessary to take measures such as using a screw having a short length in the extrusion direction or intentionally suppressing reactivity, but if the present invention is applied, good extrusion can be performed even for highly reactive materials.
[ Effect of embodiments of the invention ]
Including the aforementioned "invention effect", the following effects are achieved.
(1) The cable according to the present embodiment is provided with a sheath formed of the resin molded product according to the present embodiment, and therefore can be applied as a cable-wrapped (cable).
(2) The method for molding a resin molded product according to the present embodiment can be implemented by providing a catalyst press-in port for side feeding, and thus can be handled by a simple design change of an extruder.
(3) Since the Sn/Si is 5% or more by increasing the amount of the organotin-based crosslinking catalyst, the crosslinking rate can be further improved.
(4) The distance between the side position of the cylinder and the mold is ensured, so that sufficient kneading of the silane-crosslinkable composition and the organotin-based crosslinking catalyst can be achieved.
(5) The time for heating the silane-crosslinkable composition in the extruder can be shortened, and thus early crosslinking can be suppressed.
Examples
The present invention will be described in further detail with reference to examples, but the present invention is not limited thereto.
The materials of the resin molded articles used in examples and comparative examples were blended as shown in the following table 1 based on Chlorinated Polyethylene (CPE).
TABLE 1 compounding of resin molded article materials
As the organotin-based crosslinking catalyst, dioctyltin versatate (trade name: NEOSTANU-830 (manufactured by Nito chemical Co., ltd.) was used, and the blending amount of the organotin-based crosslinking catalyst was calculated from the ratio (%) of Cl (chlorine element), sn (tin element) and Si (silicon element) based on 100 parts by mass of the matrix material, specifically, sn/Cl and Si/Cl were calculated first, and the Sn/Si ratio was calculated.
The amounts of the catalysts (Sn/Si ratios), the scorch times T at the temperatures T of the rheometers 10 The measurement results of (2) are shown in FIG. 2.
According to FIG. 2, the scorch time T as the catalyst amount (Sn/Si ratio) and rheometer temperature T increase 10 Short, i.e., early crosslinking becomes easy to occur.
Next, the crosslinking speed k (T) at each temperature was derived from the rheometer measurement result based on the arrhenius law. The results are shown in FIG. 3.
Next, by particle method simulation (particle works), the method is derivedL/d=29, material temperature rise function T (T) in the case of an extruder with (a) - (D) 4 side feed positions. The results are shown in FIG. 4.
The results of FIGS. 3 and 4 and equation [1]]The residence time t in the extruder and the crosslinking progress were determined by introducing the catalyst side into the extruder at the respective positions (A) to (D)An example of the relationship of (2) is shown in fig. 5.
As can be seen from FIG. 5, the crosslinking progressWith the gradual increase of time, the final arrival of the extruder outlet at the crosslinking progress +.>The inhibition was lower.
The residence time t in the extruder and the final crosslinking schedule determined in this wayThe relationship of (2) is shown in FIG. 6. From FIG. 6, it was found that by shifting the side feed position to the screw front end side (D), the crosslinking progress can be finally reached even if the Sn/Si ratio is increased>The inhibition was lower.
Further, the shear velocity distribution in the extruder was derived by particle simulation. In addition, a plurality of screws having different total shear distortion amounts were produced by changing the groove depth of the full-flight screw and the length ratio of the supply unit/compression unit/metering unit.
As an example, the relationship between the residence time t in the extruder and the shear rate γ in the case of using the screws α and β is shown in fig. 7. The hatched portion in fig. 7 means the total shear distortion amount epsilon in the case of feeding from the position (D) side of fig. 4 and 5 using the screw beta.
< screw α > groove depth: 6.3mm 2.9mm (※) Length ratio of supply/compression/metering: 2:3:15
< screw β > groove depth: 6.4mm to 3.4mm (※) Length ratio of supply/compression/metering: 2:9:9
Depth of groove: the left-hand values (6.3, 6.4) are the depths of the left end portion of the screw (material inlet side), and the right-hand values (2.9, 3.4) are the depths of the right end portion of the screw (extruder outlet side). By "→" is meant that the groove depth becomes gradually shallower in the length direction of the screw from the material feed side to the extruder outlet side.
The final crosslinking progress was determined as described aboveAnd the total shear distortion ε, the surface of the extrusion molded product was observed by extruding the materials shown in Table 1 while feeding the organotin catalyst at each of positions (A) to (D) in FIGS. 4 and 5. The results are shown in FIG. 8. The molded article having good kneading and no early crosslinking was considered to be acceptable (good), and the other cases were considered to be unacceptable (x).
Progress of crosslinkingCalculated as follows.
(i) First, a temperature function T (T) in the extruder was derived by particle simulation.
(ii) Based on Arrhenius's law, the reaction rate k (T (T)) at each temperature and each time is derived.
(iii) Substituting the derived k (T)) into the aforementioned expression [1]]Calculating the outlet of the extruderValues.
As shown in fig. 8, when the catalyst was fed from a conventional hopper (material inlet 2) instead of the side feed, particles due to early crosslinking were generated (comparative example 1) when the Sn/Si ratio was 5.0%, whereas when the catalyst side was fed, good extrusion was achieved even when the Sn/Si ratio was 5.0% or more, and early crosslinking was not generated (examples 1 to 6). Among them, whether or not early crosslinking occurred was confirmed by visual inspection (the same applies hereinafter).
It was also found that by setting the side feed position to (D), even if the Sn/Si ratio was 14.9%, early crosslinking did not occur, and good extrusion was achieved (example 6). However, it was found that even if the side material position was set to (D), if the Sn/Si ratio was 18.0%, particles due to early crosslinking were generated (comparative example 4).
Furthermore, as can be seen from FIG. 8, if the extruder outlet cross-links at a rateAbove 10%, particles resulting from premature crosslinking are produced if +.>Further improvement resulted in the generation of roughness due to early crosslinking on the whole (comparative examples 1, 2, and 4).
Further, it was found that even if the Sn/Si ratio was 14.8% and the side feed position was set to (D), if the total shear distortion ε was 350, surface roughness due to insufficient kneading was generated (particles were generated in the portion of the appearance photograph in FIG. 8) (comparative example 3).
The above results show that if the crosslinking progress at the extruder outlet is to be madeWhen the total shear distortion is 10% or less and 400 or more, even if the catalyst amount is increased to increase the crosslinking rate, a cable having good appearance and no appearance defects (particles and roughness) due to early crosslinking can be obtained.
Among them, by feeding the catalyst side, the number of steps of kneading in advance can be reduced, and cost reduction can be expected.
Claims (4)
1. A molding method of a resin molded article, comprising:
a step of supplying a silane-crosslinkable resin composition containing a silane compound, which is a chlorine-based polymer as a matrix polymer, into the cylinder from a position upstream of the cylinder of the extruder,
a step of supplying an organotin-based crosslinking catalyst into the cylinder from a downstream position located downstream of an upstream position of the extruder cylinder, and
a step of preparing a kneaded material from the silane-crosslinkable resin composition and the organotin-based crosslinking catalyst, and extruding the kneaded material from a die of the extruder to mold a resin molded article;
in the step of supplying the organotin-based crosslinking catalyst, the organotin-based crosslinking catalyst is supplied by setting the content ratio of Sn from the organotin-based crosslinking catalyst to 5% or more and less than 15% by mass relative to Si from the silane compound,
in order to prevent the occurrence of "particles" or "roughness" of the 1 st poor appearance on the surface of the resin molded article by preventing early crosslinking of the kneaded product, the downstream position is set to a region of the extruder cylinder where the 1 st poor appearance does not occur,
in the region where the No. 1 appearance defect does not occur, the crosslinking progress [ phi ] of the extruder outlet is 10% or less, the crosslinking progress [ phi ] is represented by the following formula [1],
wherein t is the time (seconds) for passing through each position in the extruder when the time for feeding the material is set to 0 seconds; t (T) is the material temperature (K) at time T (sec); k (T)) is the crosslinking reaction rate at a material temperature T (T) (K) based on the arrhenius law;
in the step of supplying the organotin-based crosslinking catalyst, in order to prevent occurrence of "particles" of the 2 nd appearance failure on the surface of the resin molded article by preventing insufficient kneading of the kneaded article, the downstream position is set between the downstream end of the region where the 2 nd appearance failure does not occur and the upstream end of the region where the 1 st appearance failure does not occur,
in the region where the poor appearance of the No. 2 is not generated, the total shear distortion epsilon acting in the extruder with a single screw is more than 400, the total shear distortion epsilon is expressed by the following formula [2],
wherein γ (t) is the shear rate (seconds) at t (seconds) after being fed into the extruder －1 )，t in Time (seconds) to pass the location of side feed, t out The time (seconds) for passing the front end of the screw.
2. A resin molded article obtained by the molding method of the resin molded article according to claim 1, comprising a silane-crosslinked chlorine-based polymer, wherein the content of Sn from the organotin-based crosslinking catalyst is 5% or more and less than 15% by mass relative to Si from the silane compound, and the resin molded article has a smooth surface and a surface roughness Ra of 0.1mm or less.
3. A method for producing a cable, comprising the step of coating and molding a sheath on a cable core by the molding method of the resin molded article according to claim 1.
4. A cable obtained by the method for producing a cable according to claim 3, wherein the sheath for a cable core is formed by coating the sheath with the resin molded article according to claim 2.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017202073A JP2019073655A (en) | 2017-10-18 | 2017-10-18 | Resin molded article and molding method thereof, and electric cable and production method thereof |
| JP2017-202073 | 2017-10-18 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109679237A CN109679237A (en) | 2019-04-26 |
| CN109679237B true CN109679237B (en) | 2023-09-15 |
Family
ID=66184355
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810717273.6A Active CN109679237B (en) | 2017-10-18 | 2018-06-29 | Resin molded article, molding method thereof, cable and manufacturing method thereof |
Country Status (2)
| Country | Link |
|---|---|
| JP (2) | JP2019073655A (en) |
| CN (1) | CN109679237B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR3138627A1 (en) * | 2022-08-08 | 2024-02-09 | Nexans | Extruder for extruding an electrically insulating layer comprising a sheath having a liquid injection channel |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1412628A (en) * | 1972-06-07 | 1975-11-05 | Dow Corning Ltd | Crosslinking process |
| JPS5733804B2 (en) * | 1976-12-16 | 1982-07-19 | ||
| CN104893059A (en) * | 2014-03-04 | 2015-09-09 | 日立金属株式会社 | Silane crosslinking polyolefin resin composition, electric wire and cable |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56163132A (en) * | 1980-05-21 | 1981-12-15 | Fujikura Ltd | Crosslinking method of polychloroprene |
| JPH06103828A (en) * | 1992-09-21 | 1994-04-15 | Hitachi Cable Ltd | Polyethylene chloride sheath cable and manufacture thereof |
| JPH06103827A (en) * | 1992-09-21 | 1994-04-15 | Hitachi Cable Ltd | Polyethylene chloride sheath cable |
| JPH09208636A (en) * | 1996-02-02 | 1997-08-12 | Sekisui Chem Co Ltd | Extruder and production of silane-modified polyolefin |
| JP3224015B2 (en) * | 1996-09-06 | 2001-10-29 | 矢崎総業株式会社 | Crosslinkable vinyl chloride resin composition for covering electric wires and method for producing crosslinked vinyl chloride resin for covering electric wires |
| JP3290396B2 (en) * | 1997-12-24 | 2002-06-10 | 住友ベークライト株式会社 | Method for producing silane-crosslinked polyolefin |
| JP2008280517A (en) * | 2007-04-12 | 2008-11-20 | Hitachi Cable Ltd | Method of manufacturing non-halogen flame-retardant thermoplastic composition |
| CN101319079B (en) * | 2008-07-03 | 2010-09-29 | 聊城大学 | Silicone hydride crosslinked non-halogen flame-proof smoke-restraining polyvinyl chloride cable material and manufacturing process thereof |
| JP6706854B2 (en) * | 2016-02-12 | 2020-06-10 | 古河電気工業株式会社 | Heat-resistant cross-linked resin molded product and its manufacturing method, and heat-resistant product |
-
2017
- 2017-10-18 JP JP2017202073A patent/JP2019073655A/en active Pending
-
2018
- 2018-06-29 CN CN201810717273.6A patent/CN109679237B/en active Active
-
2021
- 2021-04-15 JP JP2021068739A patent/JP7211449B2/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1412628A (en) * | 1972-06-07 | 1975-11-05 | Dow Corning Ltd | Crosslinking process |
| JPS5733804B2 (en) * | 1976-12-16 | 1982-07-19 | ||
| CN104893059A (en) * | 2014-03-04 | 2015-09-09 | 日立金属株式会社 | Silane crosslinking polyolefin resin composition, electric wire and cable |
Also Published As
| Publication number | Publication date |
|---|---|
| JP7211449B2 (en) | 2023-01-24 |
| JP2021121665A (en) | 2021-08-26 |
| JP2019073655A (en) | 2019-05-16 |
| CN109679237A (en) | 2019-04-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5907079B2 (en) | Electric wires and cables using silane-grafted chlorinated polyethylene | |
| US4117195A (en) | Manufacture of extruded products | |
| CA2774766C (en) | Flexible, molded or extruded articles and semiconductive compounds for their manufacture | |
| EP0163865B1 (en) | One-extrusion method for making a shaped crosslinked polymeric product | |
| EP2809731B1 (en) | Thermoplastic, semiconductive compositions | |
| EP3107954B1 (en) | Polymer blends | |
| US4707517A (en) | Polymer composition | |
| JP2008280517A (en) | Method of manufacturing non-halogen flame-retardant thermoplastic composition | |
| CN109679237B (en) | Resin molded article, molding method thereof, cable and manufacturing method thereof | |
| CN107501836B (en) | Cable with a protective layer | |
| JP5845595B2 (en) | Ethylene polymer pellet and extrusion molding method using the pellet | |
| RU2440633C1 (en) | Electrically insulating cross-linking composition | |
| WO2016021611A1 (en) | Silane-grafted composition and method for producing same, as well as wire and cable using said composition | |
| JP6549928B2 (en) | Wire cable | |
| JP6187368B2 (en) | Method for producing silane-grafted chlorinated polyethylene, method for producing insulated wire, and method for producing cable | |
| JP2020027699A (en) | Cable and method for manufacturing cable | |
| JP2012256527A (en) | Silane cross-linked polyolefin insulation wire | |
| CN109438857A (en) | EP rubbers semiconductive external shield material that can be effectively crosslinked and preparation method thereof | |
| JP6504484B2 (en) | Electric wire cable and method of manufacturing silane cross-linked product, method of manufacturing electric wire, method of manufacturing cable | |
| JPH09306241A (en) | Resin composition for covering wire and manufacture of covered wire | |
| CN116622028A (en) | Silane crosslinked rubber composition, method for producing same, and electric wire and cable | |
| CN113637265A (en) | Anti-bending halogen-free flame-retardant sheath material for elevator flat cable and preparation method and application thereof | |
| JPH09157490A (en) | Polyolefin resin composition | |
| JP2018044032A (en) | Catalyst batch, wire and cable formed by using the same and manufacturing method therefor | |
| JP2017186415A (en) | Catalyst batch, wire and cable formed by using the same and manufacturing method therefor |
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 | ||
| CB02 | Change of applicant information |
Address after: Tokyo, Japan Applicant after: Bomeilicheng Co.,Ltd. Address before: Tokyo, Japan Applicant before: HITACHI METALS, Ltd. |
|
| CB02 | Change of applicant information | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |