Flame-retardant low-temperature-resistant polyvinyl chloride cable material particle and processing technology thereof

Abstract

The invention discloses flame-retardant low-temperature-resistant polyvinyl chloride cable material particles and a processing technology thereof, and belongs to the technical field of electric power materials. The invention relates to flame-retardant low-temperature-resistant polyvinyl chloride cable material particles and a processing technology thereof, and the flame-retardant low-temperature-resistant polyvinyl chloride cable material particles comprise the following formula materials: melamine polyphosphate, polyvinyl chloride, zinc oxide, lead caprylate, dioctyl phthalate, talcum powder, carbon black and 3-aminopropyltriethoxysilane. Zinc oxide, lead caprylate and dioctyl phthalate provide good temperature resistance, 3-aminopropyltriethoxysilane improves the low-temperature flexibility of the cable material, talcum powder and carbon black are added to enhance the mechanical strength of the cable material, and the polyvinyl chloride cable material particles have excellent flame retardancy and good flame retardancy. The cable has the advantages of high flexibility in a low-temperature environment, prolonged service life in harsh conditions, simple processing technology, suitableness for large-scale production, and high market application value.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical materials, and more specifically, to a flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology. Background Art

[0002] Polyvinyl chloride (PVC), as an important plastic material, is widely used in industries such as cables, construction, and automobiles due to its excellent electrical insulation, chemical corrosion resistance, and good processability. However, the performance of traditional PVC cable materials is poor in extreme environments such as high temperature, low temperature, and fire, especially in terms of flame retardancy and low-temperature toughness. With the increasing requirements for cables in industries such as electricity and communication, the improvement of the flame retardancy, low-temperature performance, and mechanical properties of PVC cable materials has become a technical problem to be solved urgently.

[0003] In the past, flame-retardant PVC cable materials mainly relied on halogen-based flame retardants or phosphorus-based flame retardants. Although halogen-based flame retardants have good flame retardant effects, their potential hazards to the environment and human health have gradually limited them. Phosphorus-based flame retardants (such as tripolyphosphate esters) have been widely studied due to their good environmental friendliness and flame retardant properties. However, traditional flame retardant technologies often neglect the improvement of the toughness of PVC in low-temperature environments and its processing performance.

[0004] With the continuous research and development of new additives, the modification technology of modern PVC cable materials has started to develop towards the direction of green environmental protection, high performance, and multi-functionality. Especially the introduction of 3-aminopropyltriethoxysilane (APTES) effectively improves the toughness of PVC at low temperatures and improves the impact resistance and brittleness resistance of cable materials in low-temperature environments. At the same time, the addition of zinc oxide not only enhances the thermal stability of PVC but also further promotes the effect of flame retardants. Summary of the Invention

[0005] The purpose of the present invention is to provide a flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology, which has excellent flame retardancy, low-temperature resistance, and mechanical properties, and is also low in cost and environmentally friendly.

[0006] A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology, characterized in that: for the flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle, the component ratio is: 40 - 60 parts of polyvinyl chloride, 20 - 30 parts of melamine polyphosphate - polyvinyl chloride, 5 - 9 parts of 3-aminopropyltriethoxysilane - polyvinyl chloride, 3 - 5 parts of zinc oxide, 1 - 2 parts of stabilizer, 6 - 10 parts of plasticizer, 3 - 5 parts of talcum powder, and 1 - 2 parts of carbon black.

[0007] Preferably, the melamine polyphosphate - polyvinyl chloride is the product of the reaction between melamine polyphosphate and polyvinyl chloride. Specifically, melamine polyphosphate and polyvinyl chloride particles are placed together in a dichloromethane solvent in a ratio of 1:0.5 - 1.5, ultrasonically mixed for 20 - 40 minutes to be uniform, 0.1 - 0.3 parts of catalyst sodium hydroxide is added, reacted at 160 - 220 °C for 30 - 60 minutes, then cooled to room temperature, and the product is washed with dichloromethane and dried.

[0008] Preferably, the 3 - aminopropyltriethoxysilane - polyvinyl chloride is the product of the reaction between 3 - aminopropyltriethoxysilane and polyvinyl chloride. Specifically, first, the polyvinyl chloride particles are sand - blasted with 120 - 180 - mesh sand, and then placed together with 3 - aminopropyltriethoxysilane in an ethanol solvent in a ratio of 0.5 - 1.5:1, ultrasonically mixed for 20 - 40 minutes to be uniform, 0.2 - 0.4 parts of catalyst aluminum chloride is added, reacted at 150 - 190 °C for 30 - 60 minutes, then cooled to room temperature, and the product is washed with ethanol and dried.

[0009] Preferably, the stabilizer is lead octoate.

[0010] Preferably, the plasticizer is dioctyl phthalate.

[0011] Preferably, the processing technology is as follows: First, polyvinyl chloride, melamine polyphosphate - polyvinyl chloride, 3 - aminopropyltriethoxysilane - polyvinyl chloride, zinc oxide, stabilizer, plasticizer, talcum powder, and carbon black are weighed according to the formula, then placed in a dryer and dried at 50 - 70 °C for 2 - 4 h. After mixing them evenly, they are transported to a twin - screw extruder for pelletizing. Control the temperature of the twin - screw extruder at 200 - 220 °C and the screw speed at 20 - 40 r / min. Then, the extruded cable material is cooled by a cooling roller to quickly drop its temperature to room temperature to form a solid material, and then cut into pellets by a pelletizer.

[0012] Compared with the prior art, the advantages of the present invention are as follows:

[0013] (1) In the present invention, melamine polyphosphate reacts with polyvinyl chloride particles to form new chemical bonds, cross - linked network structures, and hydrogen - bond network structures, forming phosphate ester groups, enabling melamine polyphosphate to be evenly dispersed between polyvinyl chlorides, thereby enhancing compatibility and binding force, improving the thermal stability, mechanical properties, and anti - aging properties of polyvinyl chloride. It can decompose at high temperature to release phosphate ions, which helps to form a fire - resistant intumescent carbonized layer, inhibit flame spread, and reduce the release of toxic gases. Moreover, at high temperature, it will also release gases such as phosphoric acid and ammonia that inhibit combustion, thus inhibiting flame propagation.

[0014] (2) In the present invention, 3-aminopropyltriethoxysilane undergoes a chemical reaction with the pretreated polyvinyl chloride particles, increasing the reaction contact area, forming a nitrogen-chlorine chemical bond and a copolymer connected by a silicon-oxygen bond (Si-O), enhancing the crosslinking degree and structural stability of the polyvinyl chloride, improving the low-temperature resistance, mechanical properties, moisture resistance and anti-aging properties of the polyvinyl chloride, and also improving the service life of the polyvinyl chloride in high-temperature and high-humidity environments.

[0015] (3) In the present invention, zinc oxide can react with hydrogen chloride generated by the thermal decomposition of polyvinyl chloride to form zinc chloride, and zinc chloride can form a transition-state carbocation in the main chain of polyvinyl chloride. This transition-state carbocation is prone to crosslinking with double bonds, thereby forming crosslinked substances between molecules, and further destroying the possibility of forming low-molecular aromatic substances by the cyclization of cis-diolefins. At the same time, zinc chloride can also promote the dehydrochlorination of polyvinyl chloride to generate a trans-polyene structure, and the trans-polyene structure cannot cyclize to form low-molecular aromatic hydrocarbon substances, thus effectively reducing the generation of smoke. And zinc oxide can also improve the anti-aging performance of polyvinyl chloride and increase the service life of polyvinyl chloride.

[0016] (4) In the present invention, the stabilizer lead octoate is beneficial to improving the thermal stability of polyvinyl chloride, preventing the decomposition of polyvinyl chloride at high temperatures, and at the same time improving the anti-aging property of polyvinyl chloride and increasing the service life of polyvinyl chloride.

[0017] (5) In the present invention, the plasticizer dioctyl phthalate can lower the glass transition temperature of polyvinyl chloride, enabling the material to maintain good flexibility in low-temperature environments and having excellent low-temperature resistance, and can improve the structural stability of polyvinyl chloride under severe cold conditions.

[0018] (6) In the present invention, talcum powder can improve the processing performance of polyvinyl chloride, increase its fluidity, contribute to the extrusion molding of cable material particles, and improve the mechanical properties of polyvinyl chloride.

[0019] (7) In the present invention, carbon black can not only improve the ultraviolet resistance of PVC, protect polyvinyl chloride from photo-degradation, but also improve its arc resistance and electrical insulation properties. The addition of carbon black can significantly enhance the conductivity and antistatic properties of the material, reducing the fault risk of polyvinyl chloride material cables under high-voltage conditions. Detailed Embodiments

[0020] Example 1:

[0021] A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology. Melamine polyphosphate and polyvinyl chloride particles are placed together in dichloromethane solvent at a ratio of 1:0.5, ultrasonically mixed for 20 minutes to be evenly mixed, 0.1 part of catalyst sodium hydroxide is added, reacted at 160 °C for 30 minutes, then cooled to room temperature, the product is washed with dichloromethane and dried to obtain melamine polyphosphate-polyvinyl chloride. First, the polyvinyl chloride particles are sandblasted with 120-mesh sand, and then placed together with 3-aminopropyltriethoxysilane in ethanol solvent at a ratio of 0.5:1, ultrasonically mixed for 20 minutes to be evenly mixed, 0.2 part of catalyst aluminum chloride is added, reacted at 150 °C for 30 minutes, then cooled to room temperature, the product is washed with ethanol and dried to obtain 3-aminopropyltriethoxysilane-polyvinyl chloride. First, 40 parts of polyvinyl chloride, 20 parts of melamine polyphosphate-polyvinyl chloride, 5 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 3 parts of zinc oxide, 1 part of stabilizer lead octoate, 6 parts of plasticizer dioctyl phthalate, 3 parts of talcum powder, and 1 part of carbon black are weighed according to the formula, then placed in a dryer and dried at 50 °C for 2 h. After mixing them evenly, they are transported to a twin-screw extruder for pelletizing. Control the temperature of the twin-screw extruder at 200 °C and the screw speed at 20 r / min, then cool the extruded cable material through a cooling roller to quickly reduce its temperature to normal temperature to form a solid material, and then cut it into particles by a pelletizer.

[0022] Example 2:

[0023] A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology. Melamine polyphosphate and polyvinyl chloride particles are placed together in dichloromethane solvent at a ratio of 1:0.75, ultrasonically mixed for 25 minutes to be uniform, 0.15 parts of catalyst sodium hydroxide is added, reacted at 175 °C for 37 minutes, then cooled to room temperature, the product is washed with dichloromethane and dried to obtain melamine polyphosphate-polyvinyl chloride. First, the polyvinyl chloride particles are sandblasted with 135-mesh sand, and then placed together with 3-aminopropyltriethoxysilane in ethanol solvent at a ratio of 0.75:1, ultrasonically mixed for 25 minutes to be uniform, 0.25 parts of catalyst aluminum chloride is added, reacted at 160 °C for 37 minutes, then cooled to room temperature, the product is washed with ethanol and dried to obtain 3-aminopropyltriethoxysilane-polyvinyl chloride. First, 45 parts of polyvinyl chloride, 22.5 parts of melamine polyphosphate-polyvinyl chloride, 6 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 3.5 parts of zinc oxide, 1.25 parts of stabilizer lead octoate, 7 parts of plasticizer dioctyl phthalate, 3.5 parts of talcum powder, and 1.25 parts of carbon black are weighed according to the formula, then placed in a dryer and dried at 55 °C for 2.5 h. After mixing them evenly, they are conveyed to a twin-screw extruder for pelletizing. Control the temperature of the twin-screw extruder at 205 °C and the screw speed at 25 r / min. Then, the extruded cable material is cooled by a cooling roller to rapidly reduce its temperature to normal temperature to form a solid material, and then cut into particles by a pelletizer.

[0024] Example 3:

[0025] A flame-retardant and low-temperature-resistant polyvinyl chloride cable compound particle and its processing technology. Melamine polyphosphate and polyvinyl chloride particles are placed together in dichloromethane solvent at a ratio of 1:1, ultrasonically mixed for 30 minutes to be uniform, 0.2 parts of catalyst sodium hydroxide is added, reacted at 190 °C for 45 minutes, then cooled to room temperature, the product is washed with dichloromethane and dried to obtain melamine polyphosphate-polyvinyl chloride. First, the polyvinyl chloride particles are sandblasted with 150-mesh sand, then placed together with 3-aminopropyltriethoxysilane in ethanol solvent at a ratio of 1:1, ultrasonically mixed for 30 minutes to be uniform, 0.3 parts of catalyst aluminum chloride is added, reacted at 170 °C for 45 minutes, then cooled to room temperature, the product is washed with ethanol and dried to obtain 3-aminopropyltriethoxysilane-polyvinyl chloride. First, 50 parts of polyvinyl chloride, 25 parts of melamine polyphosphate-polyvinyl chloride, 7 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 4 parts of zinc oxide, 1.5 parts of stabilizer lead octoate, 8 parts of plasticizer dioctyl phthalate, 4 parts of talcum powder, and 1.5 parts of carbon black are weighed according to the formula, then placed in a dryer and dried at 60 °C for 3 h. After mixing them evenly, they are transported to a twin-screw extruder for pelletizing. Control the temperature of the twin-screw extruder at 210 °C and the screw speed at 30 r / min. Then, the extruded cable compound is cooled by a cooling roller to rapidly reduce its temperature to normal temperature to form a solid material, and then cut into particles by a pelletizer.

[0026] Example 4:

[0027] A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology. Melamine polyphosphate and polyvinyl chloride particles are placed together in dichloromethane solvent at a ratio of 1:1.25, ultrasonically mixed for 35 minutes to be evenly mixed, 0.25 parts of catalyst sodium hydroxide are added, and the reaction is carried out at 205 °C for 52 minutes, then cooled to room temperature, and the product is washed with dichloromethane and dried to obtain melamine polyphosphate-polyvinyl chloride. First, the polyvinyl chloride particles are sandblasted with 165-mesh sand, and then placed together with 3-aminopropyltriethoxysilane in ethanol solvent at a ratio of 1.25:1, ultrasonically mixed for 35 minutes to be evenly mixed, 0.35 parts of catalyst aluminum chloride are added, and the reaction is carried out at 180 °C for 52 minutes, then cooled to room temperature, and the product is washed with ethanol and dried to obtain 3-aminopropyltriethoxysilane-polyvinyl chloride. First, 55 parts of polyvinyl chloride, 27.5 parts of melamine polyphosphate-polyvinyl chloride, 8 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 4.5 parts of zinc oxide, 1.75 parts of stabilizer lead octoate, 9 parts of plasticizer dioctyl phthalate, 4.5 parts of talcum powder, and 1.75 parts of carbon black are weighed according to the formula, then placed in a dryer and dried at 65 °C for 3.5 h. After mixing them evenly, they are conveyed to a twin-screw extruder for granulation. The temperature of the twin-screw extruder is controlled at 215 °C and the screw speed is 35 r / min. Then, the extruded cable material is cooled by a cooling roller to rapidly reduce its temperature to normal temperature to form a solid material, and then cut into particles by a granulator.

[0028] Example 5:

[0029] A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and its processing technology. Melamine polyphosphate and polyvinyl chloride particles are placed together in dichloromethane solvent at a ratio of 1:1.5, ultrasonically mixed evenly for 40 minutes, 0.3 parts of catalyst sodium hydroxide is added, reacted at 220 °C for 60 minutes, then cooled to room temperature, the product is washed with dichloromethane and dried to obtain melamine polyphosphate-polyvinyl chloride. First, the polyvinyl chloride particles are sandblasted with 180-mesh sand, and then placed together with 3-aminopropyltriethoxysilane in ethanol solvent at a ratio of 1.5:1, ultrasonically mixed evenly for 40 minutes, 0.4 parts of catalyst aluminum chloride is added, reacted at 190 °C for 60 minutes, then cooled to room temperature, the product is washed with ethanol and dried to obtain 3-aminopropyltriethoxysilane-polyvinyl chloride. First, 60 parts of polyvinyl chloride, 30 parts of melamine polyphosphate-polyvinyl chloride, 9 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 5 parts of zinc oxide, 2 parts of stabilizer lead octoate, 10 parts of plasticizer dioctyl phthalate, 5 parts of talcum powder, and 2 parts of carbon black are weighed according to the formula, then placed in a dryer and dried at 70 °C for 4 h. After mixing evenly, it is transported to a twin-screw extruder for pelletizing. The temperature of the twin-screw extruder is controlled at 220 °C and the screw speed is 40 r / min. Then, the extruded cable material is cooled by a cooling roller to rapidly reduce its temperature to room temperature to form a solid material, and then cut into particles by a pelletizer.

[0030] Performance test

[0031] UL 94 vertical burning test

[0032] The materials in Examples 1-5 are made into a 100 mm × 13 mm × 3 mm long strip according to the UL 94 standard, and the UL 94 vertical burning test is carried out on it using a Lab-Test Instruments UL-94 flame tester. The sample is vertically suspended in the burning tester, ensuring that the bottom of the sample is about 25 mm away from the flame nozzle, adjusting the flame height to 20 mm to 40 mm, ensuring that the flame is vertically applied to the bottom end of the sample, igniting the propane gas, and adjusting the gas flow rate to ensure a stable flame. The flame is applied to the bottom end of the sample, keeping the flame contact time for 10 seconds. After the flame is removed, observe whether the sample self-extinguishes and record the continuous burning time. If the burning does not extinguish, observe whether the sample drips burning substances and record the number of dripping substances. The following table shows the test results:

[0033]

[0034]

[0035] Limiting oxygen index detection

[0036] The materials in Examples 1 - 5 were made into a strip with dimensions of 100 mm × 10 mm × 3 mm. The limiting oxygen index of the samples was tested using a LabTest Instruments LOI Tester. The sample was installed in the combustion tube of the oxygen index tester, ensuring that the sample was vertically fixed and its bottom end was at a certain distance from the ignition source (usually 10 mm), with the surface of the sample facing upwards. The mixing ratio of oxygen and nitrogen was adjusted, starting from a low oxygen concentration (such as 21% oxygen, 79% nitrogen), and gradually increasing the oxygen concentration. The gas flow rate during the test was 200 L / h. The bottom end of the sample was ignited using a specified ignition device, and the stable combustion of the flame was maintained. The initial ignition time was usually 5 seconds. Observe the reaction of the sample under the application of the flame. Adjust the oxygen concentration repeatedly between low and high levels to find the minimum oxygen concentration at which the sample can continue to burn, which is the limiting oxygen index of the sample. Referring to the national standard GB / T 2406.2 - 2009, the following table shows the test results:

[0037]

[0038] Low-temperature brittleness detection

[0039] The materials in Examples 1 - 5 were made into a strip with dimensions of 100 mm × 10 mm × 3 mm. The low-temperature brittleness of the samples was tested using a Testometric low-temperature brittleness testing machine. The sample was installed in the low-temperature brittleness testing machine and fixed with fixtures to ensure that the sample was perpendicular to the test table. The sample was quickly cooled to -40 - 60 °C through a temperature control device or liquid nitrogen, and the sample was maintained in the low-temperature environment for at least 30 minutes to ensure that the inside of the sample reached a stable low-temperature state. Under the low-temperature environment, a bending force was slowly applied, and the temperature at the time of fracture was recorded. Referring to the national standard GB / T 15234 - 2010, the following table shows the test results:

[0040]

[0041] Tensile strength detection

[0042] The materials in Examples 1 - 5 were made into a strip with dimensions of 200 mm × 20 mm × 3 mm. The tensile strength of the samples was tested using an Instron 3300 type electronic universal testing machine. The sample was installed in the fixture of the tensile testing machine to ensure that both ends of the sample were perpendicular to the fixture and firmly fixed. The tensile speed of the testing machine was set, usually 5 mm / min. The tensile strength (maximum stress) of the sample and the elongation at break of the sample were recorded. Referring to the national standard GB / T 1040.2 - 2006, the following table shows the test results:

[0043] Example 1 Example 2 Example 3 Example 4 Example 5 Tensile strength (MPa) 21 25 28.3 22.7 19.8 Elongation at break (%) 170 190 200 180 160

[0044] Hardness detection

[0045] The materials in Examples 1-5 were made into a strip with dimensions of 60 mm × 20 mm × 3 mm. The hardness of the samples was tested using a Zwick hardness tester. The samples were fixed to the test platform of the hardness tester to ensure that the surfaces of the samples were flat and without skew. After zeroing the Zwick hardness tester, the samples were tested and the data were recorded. Referring to the national standard GB / T 2411-2008, the following table shows the test results:

[0046] Example 1 Example 2 Example 3 Example 4 Example 5 Hardness (Shore A) 71 78.33 84.67 80.33 75

Claims

1. A flame-retardant and low-temperature-resistant polyvinyl chloride cable material particle and a processing technology thereof, characterized in that: Disclosed are flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and a processing technology thereof. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles have the following component proportions: 40-60 parts of polyvinyl chloride, 20-30 parts of melamine polyphosphate-polyvinyl chloride, 5-9 parts of 3-aminopropyltriethoxysilane-polyvinyl chloride, 3-5 parts of zinc oxide, 1-2 parts of stabilizer, 6-10 parts of plasticizer, 3-5 parts of talc and 1-2 parts of carbon black.

2. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and the processing technology thereof according to claim 1 are characterized in that: The melamine polyphosphate-polyvinyl chloride is a product of the reaction of melamine polyphosphate and polyvinyl chloride. Specifically, melamine polyphosphate and polyvinyl chloride particles are placed in a dichloromethane solvent at a ratio of 1:0.5-1.5, and are uniformly mixed by ultrasonication for 20-40 minutes. 0.1-0.3 parts of catalyst sodium hydroxide are added, and the mixture is reacted at 160-220° C. for 30-60 minutes. The mixture is then cooled to room temperature, and the product is washed with dichloromethane and dried.

3. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and the processing technology thereof according to claim 1, characterized in that: The 3-aminopropyltriethoxysilane-polyvinyl chloride is a product of the reaction of 3-aminopropyltriethoxysilane and polyvinyl chloride. Specifically, polyvinyl chloride particles are first sandblasted using 120-180 mesh sandblasting, and then placed in an ethanol solvent together with 3-aminopropyltriethoxysilane in a ratio of 0.5-1.5:1, and mixed evenly by ultrasonication for 20-40 minutes, and 0.2-0.4 parts of catalyst aluminum chloride are added, and the mixture is reacted at 150-190° C. for 30-60 minutes, and then cooled to room temperature, and the product is washed with ethanol and dried.

4. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and the processing technology thereof according to claim 3 are characterized in that: The stabilizer is lead octoate.

5. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and the processing technology thereof according to claim 1, characterized in that: The plasticizer is dioctyl phthalate.

6. The flame-retardant and low-temperature-resistant polyvinyl chloride cable material particles and the processing technology thereof according to claim 1, characterized in that: The processing technology comprises the following steps: firstly weighing polyvinyl chloride, melamine polyphosphate-polyvinyl chloride, 3-aminopropyl triethoxysilane-polyvinyl chloride, zinc oxide, stabilizer, plasticizer, talcum powder and carbon black according to a formula, then placing them in a dryer, drying them at 50-70° C. for 2-4 hours, mixing them evenly and conveying them to a twin-screw extruder for granulation, controlling the temperature of the twin-screw extruder at 200-220° C. and the screw speed at 20-40 r / min, then cooling the extruded cable material by a cooling roller to rapidly reduce its temperature to room temperature to form a solid material, and then cutting it into granules by a pelletizer.

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