A method for producing a cable polypropylene filled tape

Abstract

The application belongs to the technical field of polypropylene filling belts, and discloses a production method of a cable polypropylene filling belt. The application adopts homopolymerization polypropylene resin as a base body, adds active fillers, and simultaneously carries out corona treatment and sizing. The corona treatment is helpful to the sizing. After the sizing, an isolation is formed between the cable polypropylene filling belt and the copper belt, the cable polypropylene filling belt is prevented from contacting the metal copper, the degradation of the filling belt is delayed, and therefore the filling belt is not easy to be pulverized. The filling belt is hydrophobic and heat-resistant, is light in specific gravity, is not hygroscopic, is soft and elastic, has the chemical properties of not mildewing and rotting, chemical corrosion resistance, temperature resistance and non-toxicity, has the electrical properties of soft hand feeling and no serious burrs, and has the advantages of a round cable core, improved cable mechanical buffering effect and appearance quality, enhanced cable impact resistance, and the need for filling the cable core gap during cabling. The cable filling belt is widely applied to cable filling, and can completely avoid the blackening of the copper belt caused by the filling belt.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of polypropylene filling tape, and particularly relates to a production method of a cable polypropylene filling tape. BACKGROUND

[0002] In the process of producing cable and optical cable, in order to make the cable core round, improve the mechanical cushioning effect and appearance quality of the cable, and enhance the impact resistance of the cable, the interstices of the cable core need to be filled when the cable is formed. The filling materials can be hemp rope, cotton yarn, rubber strip and polypropylene and the like. Among them, the polypropylene filling material is widely used in cable filling due to its good electrical insulation, flexibility and corrosion resistance. The performance of the polypropylene filling tape has an important influence on the cable forming performance. As the price of the filling tape is continuously declining at present, the supplier can only reduce the cost by continuously increasing the use amount of the filling master batch, so that a certain amount of high-alkaline dehumidification master batch needs to be used. The traditional process is easy to cause the water content of the filling tape to be too high, thereby causing the risk of oxidation and blackening of the copper tape. The cable is generally composed of a plurality of insulated cores twisted together, and in the process of cable formation, gaps will inevitably be generated. If these gaps are not filled with materials, the appearance of the cable will be poor, quality problems will be easily generated in subsequent processing, the surface of the finished product will be unevenly stressed, and the like. For example, the cable appearance is triangular due to poor filling; the cable gap is embedded in the sheath during extrusion; the steel belt is warped due to the non-round winding of the cable core; and the arc surface of the finished product is stressed into a linear stress during turnover or construction. Therefore, in order to make the cable round, improve the appearance quality and product quality, the gaps must be filled when the cable is formed. The technical personnel in the field urgently need to develop a production method of a cable polypropylene filling tape to meet the existing use requirements and performance requirements. SUMMARY

[0003] The application aims at the existing problems, and provides a production method of a cable polypropylene filling tape.

[0004] The production method of the cable polypropylene filling tape comprises the following steps: (1) extrusion flow casting film and wire drawing: the homopolymer polypropylene filling granules are extruded by an extruder to flow cast a film, and the polypropylene film is obtained by heat stretching, and then the polypropylene film is treated by corona discharge; (2) slitting, stretching, sizing, drying and winding: the polypropylene film treated by corona discharge is cut into a narrow strip, the surface of the narrow strip is heated to 100-110 DEG C and then stretched, the stretching multiple is 3-4 times, and the stretching speed is about 60-70 m / min; after stretching, the narrow strip is sized by a sizing machine, and then dried and wound, so that the cable polypropylene filling tape is obtained.

[0005] Further, the step (1) extruder screw diameter is 100-110mm, length-diameter ratio is 30:1-33:1, screw rotation speed is 80-100rpm, extruder power is 90-110kW, die lip length is 1000-1600mm, and production speed is 280-400m / min.

[0006] Further, the step (1) heat stretching temperature is 90-105℃, and stretching ratio is 3.5-4; extruder cylinder temperature is 165℃-175℃, 180℃-210℃, 220℃-250℃, and head temperature is 235℃-245℃.

[0007] Further, the step (2) sizing machine speed is 15-20m / min, elongation is 1.1%-1.4%, and sizing material is 25-30 parts of hydrophobic silicon dioxide added into 95-105 parts of polydimethylsiloxane solution, stirring to be paste, and the polydimethylsiloxane solution solvent is xylene, and polydimethylsiloxane content is 10%-15%wt.

[0008] The polydimethylsiloxane solution is used as a line forming agent for hammer coating in the past, and the sizing material is formed by the polydimethylsiloxane solution and hydrophobic silicon dioxide, and the surface copper belt is blackened after sizing.

[0009] Further, the step (1) corona treatment voltage is 8-10V and frequency is 50-60Hz, treatment temperature is 35-40℃, and treatment time is 10-15s.

[0010] Further, the 2.16kg, 230℃ melt flow rate of the homopolypropylene is 3-5g / 10min.

[0011] Further, the step (1) homopolypropylene filling granule contains 50-60wt% of filling agent, and the filling agent is superfine active calcium carbonate or superfine active zinc oxide.

[0012] The beneficial effects of the present application are as follows:

[0013] It is found by objective production practice that when the cable polypropylene filling tape contacts with copper, copper ions can catalyze the thermal oxidation process and accelerate the degradation of the filling tape, so the filling tape is easy to powder. The copper tape is oxidized into brown cuprous oxide and has a blackening phenomenon, and the blackening position occurs at the place in contact with the cable polypropylene filling tape. For example, aluminum hydroxide, talcum powder and the like initiate the oxidation of the copper tape, resulting in blackening of the copper tape. The cable polypropylene filling tape has poor compatibility with the copper tape, which not only causes the cable polypropylene filling tape to powder at high temperature and has poor service life, but also causes the copper tape to be oxidized and corroded, so that there is a certain safety hazard in the use of the cable. On the basis of avoiding the powdering of the cable polypropylene filling tape and preventing the blackening of the copper tape, the application adopts homopolypropylene resin as the matrix, adds active filler, and carries out corona treatment and sizing at the same time. Corona treatment is helpful to sizing. After sizing, an isolation is formed between the copper tape and the filling tape, and the filling tape is hydrophobic and heat-resistant, light in specific gravity, non-hygroscopic, soft and elastic, and has the following chemical properties: no mildew, chemical corrosion resistance, temperature resistance, non-toxicity, and the following electrical properties: soft hand feeling, no serious burr, round cable core, improved cable mechanical buffering effect and appearance quality, enhanced cable impact resistance, and the like. The cable core gap needs to be filled when cabling, and the filling tape is widely used in cable filling and can completely avoid the blackening of the copper tape caused by the filling tape. DETAILED DESCRIPTION

[0014] The application will be described in detail below with specific examples, but is not limited to the application. Example 1

[0015] Raw materials and equipment: CF012000 super-fine active calcium carbonate, 2.16 kg, melt flow rate at 230℃ of 3g / 10min, T30S homopolypropylene containing 50wt% of super-fine active calcium carbonate, homopolypropylene filling granules; Yongming SJPL-100X33-1100X2, extruder screw diameter 100mm, length-diameter ratio 33:1, screw rotation speed 100rpm, extruder power 90kW, die lip length 1000mm, production speed 280m / min; winding line speed 100m / min; QJ-DY corona treatment machine; HB-612 hydrophobic silica; Xingjinpeng 201-500 polydimethylsiloxane.

[0016] The production method of the cable polypropylene filling tape comprises the following steps: (1) extrusion flow casting film and drawing: the homopolymer polypropylene filling pellets are extruded flow casting film by an extruder, and polypropylene film is obtained by hot stretching, the hot stretching temperature is 90℃, and the stretching ratio is 3.5; the temperature of each section of the extruder cylinder is 165℃, 180℃ and 220℃, and the die head is 235℃. Then the polypropylene film is treated by corona, the corona treatment voltage is 8V-10V, the frequency is 50Hz-60Hz, the treatment temperature is 35℃, and the treatment time is 10ss; (2) slitting, stretching, sizing, drying and winding: after the polypropylene film treated by corona is cut into a narrow strip, the surface of the narrow strip is heated to 100℃ and then stretched, the stretching multiple is 3 times, and the stretching speed is about 60-70m / min; after stretching, the narrow strip is sized by a sizing machine, the sizing machine speed is 15m / min, the elongation rate is 1.1%, the sizing agent is 25 parts of hydrophobic silicon dioxide added into 95 parts of polydimethylsiloxane solution, and stirring is performed until the sizing agent is in a paste state, and the polydimethylsiloxane solution is obtained, wherein the solvent of the polydimethylsiloxane solution is dimethylbenzene, and the polydimethylsiloxane content is 10wt%; and the polydimethylsiloxane solution is dried at 130℃ for 10min and wound, and the cable polypropylene filling tapes with the widths of 1.5mm, 2.5mm, 4.04.5mm, 5.5mm and 7.0mm are obtained.

[0017] The product performance is: dry, no pollution, no impurities, uniform color, and the thermal aging performance is that after 7 days of continuous aging test at 100℃, the filling tape is gently rubbed by hand, and no obvious powdering and breaking phenomenon occurs. The heat shrinkage performance is that after 1 hour of continuous aging test at 100℃, the length shrinkage rate of the sample is ≤10%. The compatibility is that the copper tape surface is not blackened after aging. The water content is ≤1.0%. Example 2

[0018] Raw materials and equipment: Zongle Chemical Superfine Active Zinc Oxide, 2.16kg, the melt flow rate of the melt at 230℃ is 5g / 10min, ST30 homopolymer polypropylene containing 50wt% of superfine active zinc oxide homopolymer polypropylene filling pellets; Yongming SJPL-110×30-1100X2, the screw diameter of the extruder is 100mm, the length-diameter ratio is 30:1, the screw rotation speed is 80rpm, the power of the extruder is 110kW, the die lip length is 1000mm, and the production speed is 400m / min; the winding line speed is 100m / min; QJ-DY corona treatment machine; HB-630 hydrophobic silicon dioxide Xingjinpeng 201-500 polydimethylsiloxane.

[0019] The production method of the cable polypropylene filling tape comprises the following steps: (1) extrusion flow casting film and drawing: homopolymer polypropylene filling pellets are extruded flow casting film through an extruder, and polypropylene film is obtained through heat stretching, the heat stretching temperature is 105℃, and the stretching ratio is 4; the temperature of each section of the cylinder of the extruder is 175℃, 210℃ and 250℃, and the die head is 245℃. Then the polypropylene film is treated by corona treatment, the corona treatment voltage is 10V, the frequency is 60Hz, the treatment temperature is 40℃, and the treatment time is 15s; (2) slitting, stretching, sizing, drying and winding: after the polypropylene film treated by corona treatment is cut into a narrow strip, the surface of the narrow strip is heated to 110℃ and then stretched, the stretching multiple is 4, and the stretching speed is about 60-70m / min; after stretching, sizing is performed by using a sizing machine, the sizing machine speed is 20m / min, the elongation rate is 1.4%, and according to the weight fraction, 30 parts of hydrophobic silicon dioxide is added to 105 parts of a polydimethylsiloxane solution, and stirring is performed until the polydimethylsiloxane solution is in a paste state, namely, the polydimethylsiloxane solution solvent is xylene, and the polydimethylsiloxane content is 15wt%; and the polydimethylsiloxane solution is dried at 120℃ for 15min, and then wound, so that the cable polypropylene filling tapes with the widths of 2.0mm, 3.0mm, 4.5mm, 5.5mm, 6.5mm and 8.0mm are obtained, and the cable polypropylene filling tapes are obtained.

[0020] The product performance is: dry, non-polluted, non-impure, uniform color, and the thermal aging performance is that after 7-day continuous aging test at 100℃, the filling tape is gently rubbed by hand, and no obvious powdering and breaking phenomenon occurs. The thermal shrinkage performance is that after 1-hour continuous aging test at 100℃, the sample length shrinkage rate is ≤10%. The compatibility is that the copper tape surface is not blackened after aging. The water content is ≤1.0%.

[0021] The performance of the cable polypropylene filling tapes with various width specifications in example 1 and example 2 is detected, and the detection results are shown in table 1.

[0022] Table 1: performance detection results of the cable polypropylene filling tapes with various width specifications in example 1 and example 2

[0023]

[0024] Comparative example 1

[0025] Compared with example 1, the superfine active calcium carbonate used in step (1) of the comparative example is replaced by an equal amount of ordinary heavy calcium carbonate LD-800, and the remaining steps are the same.

[0026] Comparative example 2

[0027] Compared with example 1, the polypropylene film is not treated by corona treatment in step (1) of the comparative example, and the remaining steps are the same.

[0028] Comparative example 3

[0029] Compared with Example 1, the step (2) of the comparative example is not carried out on the sizer, and the remaining steps are the same.

[0030] Comparative Example 4

[0031] Compared with Example 1, the step (1) of the comparative example uses superfine active calcium carbonate instead of an equal amount of ordinary Zhongyang Jinghua WF-2 talc, and the remaining steps are the same.

[0032] Comparative Example 5

[0033] Compared with Example 1, the step (1) of the comparative example uses superfine active calcium carbonate instead of an equal amount of ordinary Zhonghai Xinxuan's H-WF-1 aluminum hydroxide, and the remaining steps are the same.

[0034] The cable polypropylene filled tape heat aging and copper tape connection material surface of Examples 1-2 and Comparative Examples 1-5 was sealed after being immersed in water for 10S and placed in a 00C heating environment. The specific comparison results are shown in Table 2.

[0035] Table 2 Heat aging and copper tape contact test results of cable polypropylene filled tape of Examples 1-2 and Comparative Examples 1-5

[0036]

[0037] Note: The breaking force test method is tested under the test environment of temperature 23℃, humidity 50%. Single strand can be cut from the distance of 2m above the roll head, the sample length is 500mm, the stretching rate is 100mm / min, 3 samples are tested to calculate the arithmetic mean value; the heat shrinkage test method: sample preparation: take at least 250mm length of the filler tape sample, measure about 200mm length with a ruler, accurate to 0.5mm, use the line distance between the two ends as the standard length, recorded as L0 (unit: mm), put the sample into the aging test box at 100℃, take out the sample after 1h, measure the distance between the sample mark lines after cooling to room temperature; heat aging test method: heat the heat aging test box (the aging box should meet the requirements of GB / T2951.12-2008 8.1.2) to the required temperature of the test 100℃. Take 500mm sample, roll into a circular ring with a diameter of about 100mm, tie the two places on the same cross section of the circular ring with nylon rope. Hang the tied sample in the heat aging test box. Compatibility test method: take a 300mm long sample, immerse it in water for 10s after unfolding the crease, wrap it on a copper tape with a length of 150mm and a width of 50mm, and cover the wrapped part with the copper tape that has not been wrapped, and fix it with copper wire. Immerse the wrapped sample in water again for 10s, and put it into a conical flask, seal it with tin paper and fix it. Put the sealed conical flask into a heat aging test box (the aging box should meet the requirements of GB / T2951.12-2008 8.1.2) at 100℃ and heat for 4h; take out the test sample, untie the copper tape, and observe whether the copper tape has oxidation and blackening phenomenon. The test copper tape should meet the requirements of GB / T11091.

Claims

1. A method for producing a cable polypropylene filled tape, characterized by, The method comprises the following steps: (1) extrusion casting film forming and drawing: homopolymer polypropylene filling granules containing 50-60 wt% of a filler, the filler being superfine active calcium carbonate or superfine active zinc oxide, are extruded by an extruder to form a film, and the film is hot-drawn to obtain a polypropylene film, which is then subjected to a corona treatment at a voltage of 8-10 V, a frequency of 50-60 Hz, a temperature of 35-40 °C, and a time of 10-15 s; (2) slitting, drawing, sizing, drying, and winding: the polypropylene film after the corona treatment is cut into narrow strips, which are then drawn after being heated to 100-110 °C, with a draw ratio of 3-4 and a drawing speed of about 60-70 m / min; the drawn strips are sized by a sizing machine at a speed of 15-20 m / min and an elongation of 1.1-1.4%, and the sizing agent is prepared by mixing 25-30 parts of hydrophobic silicon dioxide with 95-105 parts of a polydimethylsiloxane solution, stirring until a paste is obtained, and drying and winding the paste to obtain a cable polypropylene filling tape, wherein the solvent of the polydimethylsiloxane solution is xylene, and the content of polydimethylsiloxane is 10-15 wt%.

2. The method of producing a cable polypropylene filled tape according to claim 1, characterized in that, The screw diameter of the extruder in step (1) is 100-110 mm, the length-diameter ratio is 30:1-33:1, the screw rotation speed is 80-100 rpm, and the production speed is 280-400 m / min.

3. The method of producing a cable polypropylene filled tape according to claim 1, characterized in that, The temperature for the hot drawing in step (1) is 90-105 °C, and the draw ratio is 3.5-4; the barrel temperature of the extruder is 165-175 °C, 180-210 °C, or 220-250 °C, and the die head temperature is 235-245 °C.

4. The method of producing a cable polypropylene filled tape according to claim 1, characterized in that, The 2.16-kg melt flow rate at 230 °C of the homopolymer polypropylene is 3-5 g / 10 min.

Images