2 thoughts on “Do all the materials in the handboard industry use plastic?”
Opal
Handboard material-usually use plastic material performance . ABS: acrylin -butadiene -phenyl polymer 1. The role of the three ingredients Pylene Qing (A) -The high hardness of the product and improved wear resistance. Tiene (B) -This to strengthen softness and maintain material toughness, elasticity and impact resistance. The styrene (S) -The maintain good formation (liquidity coloring) and maintain the rigidity of the material (note that there are multiple specifications according to different components). 2. ABS has good electroplating and is the best plating among all plastic. 3. ABS has significantly improved the impact strength of GPPS. 4. ABS raw materials are light yellow and opaque, and the surface of the product is good. 5. ABS has a small contraction and stable size. 6. Inaulte -resistant solvents: such as soluble ketones, aldehyde, esters, and oxide hydrocarbons to form milk turbid flow (ABS glue). 7. Materials mixing performance: ABS PVC ~~~ Improving toughness, combustion resistance, anti -aging. abs PC ~~~ Improve the impact strength and heat resistance. abs for molding technology 1. Before the formation processing, it is necessary to fully dry, so that the water content is u003C0.1%, the temperature of the drying conditions is 85 ° C, and the time is 3HRS. 2. ABS has a good liquidity and is easy to produce beer -plastic wizards. The injection pressure is 70 ~~ 100MPa, which should not be too large. 3. The temperature of the tube is not easy to exceed 250 ° C The front tube 160 ~~~ 210 ° C, the middle grip is 170 ~~~ 190 ° C, and the rear cylinder 160 ~~~ 180 ° C too high temperature will cause the decomposition of plastic ingredients and move the flow to move the flow. Reduction. 4. The mold temperature is 40 ~~ 80 ° C, the appearance requirements are high, and the mold temperature should be high. 5. The injection speed is mainly medium and low speed. Injection 80 ~~ 130MPa. 6. ABS internal stress inspection: It is based on the cracked tattoo of the product in the kerosene for 2 minutes. . MBS -Transparent ABS, Polymethylene -butadiene -lyerene cluster. The main properties: transparent, toughness, acid and alkali resistance, good liquidity, easy to form color, stable size. . SBS -K material (transparent). Tutonne and ethylene polymer (KR01, KR03). Main nature: transparent, good elasticity, and convenient molding. . PS material: polystyrene (GPPS hard glue, HIPS modified polyethylene GPPS -hard HIPS -not broken. a) add an appropriate amount (5 ~~ 20%) butadiene rubber modification in GPPS , Thereby improving the impact of hard glue. b) Color: GPPS-high transparency, high-sex, HIPS-opaque milk white or slightly yellow. c) HIPS and GPPS can be mixed with beer plastic as needed. The more GPPS ingredients, the better the surface of the product, and the liquidity The better. HIPS: GPPS = 7: 3 or 8: 2 can maintain sufficient strength and surface quality. The molding process of polyethylene ethylene 1. GPPS has a large temperature range (the molding temperature is far degradable temperature) heating flow and the fast curing speed, so the molding cycle is short. Under the premise of being full of cavity, the temperature of the tube should be slightly bottomed, the temperature of the front grip is 200 ° C, and the rear material should be material. Tube 160 ° C. 2. GPPS has good liquidity, and does not require high beer plastic pressure (70 ~~~ 130pma) pressure in the molding. (Modified PS is that HIPS liquidity is slightly worse than GPPS). 3. The injection speed should be higher to weaken the melting marks (watery pattern), but the injection speed is greatly affected by the injection pressure, and the high speed of high speed may produce flying edges (piercing front) or crushing when molding. 4. Model temperature: 30 ℃ ~~ 50 ℃. 5. Polystyeyrene (GPPS) is small due to small hygroscopicity. Generally, no bathing before forming, and the modified polystyrene (HIPS) must dry at 60 ° C ~~ 80 ° C to dry time 2HRS. . The main properties of polypropylene (PP) — percentage, crystalline plastic are as follows: 1. It can float in water in a translucent color and light quality (density 0.91). 2. Good liquidity and moldability, surface luster, (leaving trace in PE). 3. The high molecular weight makes the tensile strength high yield strength (fatigue). 4. High chemical stability, difficulty in organic solvents, fuel injection, hotness, and bonding difficulties. 5. Different wear resistance and good impact resistance at normal temperature. 6. The size of the molding contraction (1.6%) is unstable, and the glue is easy to deform and shrink. The forming process of polypropylene (PP material) 1. The fluidity of polypropylene is good, and the lower injection pressure can be full of cavity. The pressure is too high to produce flying edges, but too low shrinkage will be severe. The injection pressure is generally about 80%of the pressure of 80 ~~~ 90MPa. 2. Suitable for fast injection, in order to improve the exhaust, and the exhaust tank should be slightly deepened by 0.3mm. 3. High crystalline degree of polypropylene, anterior tube of 200 ~~~ 240 ° C, 170 ~~~ 220 ° C in the middle ingredient, 160 ~~ 190 ° C in the rear cylinder, due to the large temperature range of its molding Batch and shrink to use lower temperatures. 4. Due to the high contraction rate of materials and the size of accurate control, the cooling time should be appropriately extended. 5. Modern temperature is easy to take low temperature (20 ~~~ 40 ° C) Modern temperature is too high to make the crystallization, strong inter -molecular effect, good rigidity, good gloss, but poor softness, poor transparency, and shrinking obviously. 6. The back pressure should be 0.1MPa. The dry powder color process should be appropriately improved to improve the mixed effect. . Polyvinyl chloride (PVC) The polyvinyl chloride (PVC) is a non -crystalline plastic and raw material transparent. The main performance is as follows 1. By adding plasticizers to make the material’s soft and hardness range. 2. Difficult self -extinguishing and poor thermal stability. 3. PVC is dissolved in ethyragone, hydrogen sutu, dichloroethane, and soft glue oil water (including ethyragone) for soft glue. 4. PVC is mainly used for enamel (and as a doll). The molding process of polyvinyl chloride (PVC) understands 1. Soft PVC contraction rate (1.0 ~~ 2.5%) PVC polarity molecules are easy to absorb water, dry before forming, dry temperature 85 ~~ 95 ° C, 2 hours. 2. During the formation, the tube has been heated for a long time, and the chlorine chloride monomer and HCL (that is, degradation) are decomposed, so the dead corners of the mold cavity and the head of the head should be often cleaned. 3. Add ABS to soft PVC to improve toughness, hardness and mechanical strength. 4. Because the machining temperature of PVC is close to the decomposition temperature, the tube temperature should be strictly controlled, and the molding temperature should be used as low as possible. At the same time, the molding cycle should be shortened at the same time to reduce the residence time of the soluble in the tube. The temperature parameters of the tube, the front barrel 160 ~~~ 170 ° C mid -tube 160 ~ 165 ° C rear cylinder 140 ~~ 150 ° C. 5. For easy decomposition, poor liquidity, the mold runways and ports are as short as possible, thick to reduce the loss of less pressure and the as soon as possible, the cavity -type cavity injection pressure MPA should use high pressure and low temperature injection, back pressure 0.5 ~~ 1.5MPa, PVC products wall wall The thickness should not be too thin, and it should be above 1.5mm, otherwise it is difficult to charge the cavity. 6. The injection speed should not be too fast, so as to avoid strenuous friction when the solution is poured, so that the temperature will rise, and it is easy to cause shrinkage marks. 7. The mold temperature is as low as possible (about 30 ~~~ 45 ° C) to shorten the molding cycle and prevent the formation of the formation of the formation (the time the glue must be fixed by the format). 8. In order to prevent cold materials from blocking the mouth or inflowing into the mold cavity, a large cold material shaft should be designed. seven. Polytealdehyde (POM Steel) The formaldehyde (POM) is commonly known as Cymbicon Crystal Plastics. The main performance is as follows: 1. Polytealdehyde is a milky white and shiny plastic. 2. It has comprehensive mechanical properties, high hardness rigidity, good impact resistance, and excellent abrasion resistance and self -lubrication. 3. Organic solvents have good performance and stable performance. 4. After molding, the size is relatively stable and the temperature environment is less affected. POM’s formaldehyde forming technology 1. Polytealdererdide hygroscopic (water absorption rate u003C0.5%) generally does not take a bath or a short bath before forming. 2. The molding temperature range is narrow, the thermal stability is poor, and the formaldehyde unit (darker of the melt color becomes darker) above 250 ° C. Therefore, it improves the temperature and the liquidity is harmful and invalid. Normal beer plastic should use lower tube temperature and short retention time, and improving injection pressure can improve the liquidity of the melt and the surface quality of the product. (Mel is more sensitive to cutting speed). Temperature parameters: The front barrel 190-210 ℃ Middle tube 180-205 ℃ The tube 150-170 ℃. Press the pressure parameters: The injection pressure is about 100MPa, and the back pressure is 0.5MPa. 3. Mold temperature: 80-100 ° C is appropriate (generally air transport oil). 4. The POM cooling contraction rate is very large (2 ~~ 2.5%). It is easy to reduce the shrinkage of beer plastic. eight, polyethylene (PE) “flower material” The polyethylene (PE) commonly known as “flower material” is crystalline plastic. The main properties are as follows: 1. The polyethylene is divided into two types: high -density (HPPE) sub -density (HPPE) and low -degree (LPPE), which weakens as the density is high and transparent. 2. Polyethylene is a translucent particle, and the appearance of the glue is milky. 3. Polyethylene has softness, impact resistance, extension and abrasion resistance, and low temperature toughness. 4. It does not melt at any melt at room temperature, and the chemical performance is stable and PE is difficult to bond. 5. The mechanical strength is not high, the thermal deformation temperature is low, and the surface is easy to scratch. 6. Polyethylene (PE) is often used for blowing plastic products. The formation process of polyethylene 1. Good liquidity, a wide range of molding temperature, and easy to mold. 2. Injecting pressure and pressure should not be too high, avoiding large stress in the beer parts and causing deformation and cracking, the injection pressure is 60 ~~ 70MPa. 3. Dry treatment is not required before water absorption. 4. The temperature and quality of the tube is improved, but the molding rate of molding (2 ~~ 2.5%) The temperature of the barrel is too low to deform (more severe pouring out of the mouth, use multiple points to improve the warp), the temperature parameters of the temperature, and the temperature parameters : 200 ~ 220 ° C in front of the leaflet, 180 ~~ 190 ° C in the middle grip, 160 ~~ 170 ° C in the rear cylinder. 5. The front and rear mold temperatures are consistent (the mold temperature is generally 20 ~~ 40 ° C is suitable) cooling water should not be too close to the surface of the cavity, so as not to avoid the local temperature difference, so that the product residues internal stress. Improve the mold temperature, good product gloss, but long molding cycle. Reduce mold temperature, product softness and high transparency, high impact strength, too low and cold, causing product deformation or molecular orientation, in short, the hardness and flexibility of the product can be adjusted by adjusting the mode temperature. 6. Because the quality is soft, it is forcibly demolished without row (slider) when it is necessary. . The polycarbonate (PC) (the most expensive) Carbonate (PC) is commonly known as “bulletproof glass glue”. The appearance is transparent, the rigid is tough, the combustion is slow, and the fire is off after the fire. 2. PC material impact is the best in plastic. 3. The molding rate (0.5 ~~ 0.7%) has a high accuracy and high size stability. 4. Chemical stability is good, but it is not resistant to alkali, ketone, aromatic hydrocarbons and other organic melts. 5. Fatigue resistance is sensitive to gaps. Carbonate (PC) molding process 1. PC is very sensitive to micro water. Before molding, the water content should be fully dry at 0.015%drying temperature 110 ~~ 120 ° C and 12HRS. 2. Poor liquidity and high pressure injection molding, but the injection molding pressure is too high, which will cause the product to remain large internal stress, and it is easy to crack 3. The viscosity of PC is very sensitive to temperature, and the temperature viscosity decreases. The front cylinder is 240 ~~ 260 ° C, 260 ~~ 280 ° C, and the rear cylinder 220 ~~~ 230 ° C does not exceed 310 ° C. 4. Mold design requirements This rumors, flowing channel polishing, cavity and stamens should quench or hard chromium. 5. The injection speed is too fast, the solubility is easy to break, the pouring mouth is vague, and the exhaust (difficulty) burns the product. 6. Modern temperature 80 ~~ 100 ° C. 7. Under annealing treatment, 125 ~~ 135 ° C 2HRS, naturally cooling to room temperature. Ten, polyamide (PA) nylon material The polyamide is commonly known as “nylon” (Nylon), which belongs to crystalline plastics, such as nylon 6, nylon 66, nylon 1010 and so on. 1. Nylon has good toughness, abrasion resistance, durability, self -lubricating and self -extinguishing. 2. Good low temperature performance, high impact strength, and high tensile strength, good elasticity. 3. The nylon water absorption is large, and the tensile strength is increased to a certain extent after absorbing, but the contraction rate of other intensity (such as stretching, stiffness) is 0.8 ~~ 1.4%. 4. For weak acid, weak alkali and general solvents, the saturated methanol solution can also be dissolved in phenols (phenols can be used as adhesives) at normal temperature. Newy molding process 1. Before injection, it needs to be fully dry. The drying temperature is 80 ~~ 90 ° C, and the drying time is 24HRS. 2. Nylonic viscosity, good liquidity, and prone to the pressure (flying edge) pressure is not too high, generally 60 ~~ 90MPa. 3. With the temperature of the barrel, the contraction rate fluctuates and highly fluctuated. The nylon material below the melting temperature is very stingy, which will damage the loop mold and screw. The temperature of the tube is generally 220 ~~ 250 ° C, and it should not exceed 300 ° C. 4. Mode temperature control: Nylon is a crystalline plastic, and the product is highly affected by the mold temperature. Themore temperature: Large crystallinity, rigidity, and abrasion resistance increases less. This temperature is low: good flexibility, high elongation rate, small contraction rate, and the mold temperature is controlled at 20 ~~ 90 ° C. 5. High -speed injection: This nylon melting point is high and the solidification point is high (fast molding, high production efficiency) is a smooth charging mold (do not reduce the melt to the melting point). The product dragon is thicker or overflowing with the thickness of the product. 6. Antuction treatment and temperature adjustment. a annealing treatment: After the annealing, the crystallization can increase, the rigidity increases, it is not easy to deform and crack. b temperature adjustment processing: maintain stable size, which is good for improving the toughness and improvement of the internal stress distribution. Temperature adjustment method: immerse boiled water or potassium acetate solution. Potassium: water = 1.25: 100 time 2 ~~ 16HRS. The polyethylene acrylic (PMMA) MAA “Agree”, which is organic glass, is a non -crystalline plastic 1. High transparency, light quality is not easy to deform, good light guide. 2. PMMA is difficult to get angry and can burn slowly. 3. Inflictter -resistant, powerful alkali, can be dissolved in aromatic hydrocarbons and chlorine chloride (methane can be used as adhesive). 4. Easy to mold and stable size. 5. The impact resistance and surface hardness are slightly worse, and it is easy to control the flowers, so it has higher requirements for packaging. PMM for molding process: 1. Aga Li’s transparency is high, beer plastic defects such as bubbles, flow patterns, impurities black spots, silver wires, etc. are obviously exposed, so the difficulty of forming difficulty high products is low 2. The raw materials are fully dry, the drying of silver silk air bubbles, etc. Drying conditions: Temperature 95 ~~~ 100 ° C 6HRS material layer thickness does not exceed 30mm, and the fight should continue to keep warm to avoid re -blowing. 3. The liquidity is poor, it should be formed at high pressure, the injection pressure is 80 ~~ 100MPa. The pressure preservation pressure is about 80%of the injection pressure, and the back pressure should not be high to prevent early cooling of the flowing track. 4. The injection speed The injection speed has a great impact on viscosity. Do not be too fast. If the injection speed is too high, it will cause plastic foam, burnt, and poor transparency. If the injection pressure is too low, it will make the product’s solid line thicker. 5. The material temperature The liquidity increases with the temperature of the tube, but under the premise of being able to fill the cavity, the temperature should not be too high to reduce color change, silver wire and other defects, the front cylinder is 200 ~~~ 230 ° C, 215 ~~ 235 ° C, and rear pipes 140 ~~~ 160 ° C. 6. High mold temperature, high product transparency, and reducing poor fusion, especially reducing the internal stress of the product, and easy to fill the cavity, the mold temperature is generally 70 ~~ 90 ° C. 7. The design of the mold should be brief, smooth, and the wide pouring mouth is formed. 8. Reduce the internal stress The thermal treatment temperature of 70 ~~ 80 ° C, hot air or water cold time is generally 4HRS. 9. Reduce beer and plastic black spots a to ensure clean raw materials (environmental cleaning). B cleaning mold. C machine cleaning (the front end of the cleaning tube, screw, nozzle). 10. The mold surface is kept clean, and the plating is used to resist corrosion. Try not to use the mold as little as possible to increase the mold slope of the mold and facilitate the molding.
The four categories of commonly used plastic handboards because the products produced by the enterprises are different every day, the handbued models needed to be made are different. The following: 1. ABS handboard models are generally widely used in product shells, and they are relatively integrated. Most of them are used in metal plated products, such as hydraulugulaton, vacuum steaming electrical plating, and the models of their materials have round sticks , Board, etc. 2. PMMA is an acrylic, also an organic glass. It has good transparency and is the best material for the production of transparent products. It is used for products with strong solubility, but its stronghold is relatively crispy. And it is suitable for institutions with cardiac hooks. 3. PP is a translucent material. Its advantage is that it is very resistant to impact, strong impact resistance, and it is also very flexible to belong to it. Products, such as car accessories, packaged as a folding handboard model. 4. PC is a product with good strength, high flexibility, and very good transparency. His advantages are set. In addition, it also adds glass fiber to improve steel and heat resistance. The plate materials are more suitable for Lens. The first choice and production of fine products requires the handboard model of production products that still maintain steel in high temperature environments.
Handboard material-usually use plastic material performance
. ABS: acrylin -butadiene -phenyl polymer
1. The role of the three ingredients
Pylene Qing (A) -The high hardness of the product and improved wear resistance.
Tiene (B) -This to strengthen softness and maintain material toughness, elasticity and impact resistance.
The styrene (S) -The maintain good formation (liquidity coloring) and maintain the rigidity of the material (note that there are multiple specifications according to different components).
2. ABS has good electroplating and is the best plating among all plastic.
3. ABS has significantly improved the impact strength of GPPS.
4. ABS raw materials are light yellow and opaque, and the surface of the product is good.
5. ABS has a small contraction and stable size.
6. Inaulte -resistant solvents: such as soluble ketones, aldehyde, esters, and oxide hydrocarbons to form milk turbid flow (ABS glue).
7. Materials mixing performance:
ABS PVC ~~~ Improving toughness, combustion resistance, anti -aging.
abs PC ~~~ Improve the impact strength and heat resistance.
abs for molding technology
1. Before the formation processing, it is necessary to fully dry, so that the water content is u003C0.1%, the temperature of the drying conditions is 85 ° C, and the time is 3HRS.
2. ABS has a good liquidity and is easy to produce beer -plastic wizards. The injection pressure is 70 ~~ 100MPa, which should not be too large.
3. The temperature of the tube is not easy to exceed 250 ° C
The front tube 160 ~~~ 210 ° C, the middle grip is 170 ~~~ 190 ° C, and the rear cylinder 160 ~~~ 180 ° C too high temperature will cause the decomposition of plastic ingredients and move the flow to move the flow. Reduction.
4. The mold temperature is 40 ~~ 80 ° C, the appearance requirements are high, and the mold temperature should be high.
5. The injection speed is mainly medium and low speed. Injection 80 ~~ 130MPa.
6. ABS internal stress inspection: It is based on the cracked tattoo of the product in the kerosene for 2 minutes.
. MBS -Transparent ABS, Polymethylene -butadiene -lyerene cluster.
The main properties: transparent, toughness, acid and alkali resistance, good liquidity, easy to form color, stable size.
. SBS -K material (transparent). Tutonne and ethylene polymer (KR01, KR03).
Main nature: transparent, good elasticity, and convenient molding.
. PS material: polystyrene (GPPS hard glue, HIPS modified polyethylene GPPS -hard HIPS -not broken.
a) add an appropriate amount (5 ~~ 20%) butadiene rubber modification in GPPS , Thereby improving the impact of hard glue.
b) Color: GPPS-high transparency, high-sex, HIPS-opaque milk white or slightly yellow.
c) HIPS and GPPS can be mixed with beer plastic as needed. The more GPPS ingredients, the better the surface of the product, and the liquidity
The better. HIPS: GPPS = 7: 3 or 8: 2 can maintain sufficient strength and surface quality.
The molding process of polyethylene ethylene
1. GPPS has a large temperature range (the molding temperature is far degradable temperature) heating flow and the fast curing speed, so the molding cycle is short. Under the premise of being full of cavity, the temperature of the tube should be slightly bottomed, the temperature of the front grip is 200 ° C, and the rear material should be material. Tube 160 ° C.
2. GPPS has good liquidity, and does not require high beer plastic pressure (70 ~~~ 130pma) pressure in the molding. (Modified PS is that HIPS liquidity is slightly worse than GPPS).
3. The injection speed should be higher to weaken the melting marks (watery pattern), but the injection speed is greatly affected by the injection pressure, and the high speed of high speed may produce flying edges (piercing front) or crushing when molding.
4. Model temperature: 30 ℃ ~~ 50 ℃.
5. Polystyeyrene (GPPS) is small due to small hygroscopicity. Generally, no bathing before forming, and the modified polystyrene (HIPS) must dry at 60 ° C ~~ 80 ° C to dry time 2HRS.
. The main properties of polypropylene (PP) — percentage, crystalline plastic are as follows:
1. It can float in water in a translucent color and light quality (density 0.91).
2. Good liquidity and moldability, surface luster, (leaving trace in PE).
3. The high molecular weight makes the tensile strength high yield strength (fatigue).
4. High chemical stability, difficulty in organic solvents, fuel injection, hotness, and bonding difficulties.
5. Different wear resistance and good impact resistance at normal temperature.
6. The size of the molding contraction (1.6%) is unstable, and the glue is easy to deform and shrink.
The forming process of polypropylene (PP material)
1. The fluidity of polypropylene is good, and the lower injection pressure can be full of cavity. The pressure is too high to produce flying edges, but too low shrinkage will be severe. The injection pressure is generally about 80%of the pressure of 80 ~~~ 90MPa.
2. Suitable for fast injection, in order to improve the exhaust, and the exhaust tank should be slightly deepened by 0.3mm.
3. High crystalline degree of polypropylene, anterior tube of 200 ~~~ 240 ° C, 170 ~~~ 220 ° C in the middle ingredient, 160 ~~ 190 ° C in the rear cylinder, due to the large temperature range of its molding Batch and shrink to use lower temperatures.
4. Due to the high contraction rate of materials and the size of accurate control, the cooling time should be appropriately extended.
5. Modern temperature is easy to take low temperature (20 ~~~ 40 ° C) Modern temperature is too high to make the crystallization, strong inter -molecular effect, good rigidity, good gloss, but poor softness, poor transparency, and shrinking obviously.
6. The back pressure should be 0.1MPa. The dry powder color process should be appropriately improved to improve the mixed effect.
. Polyvinyl chloride (PVC)
The polyvinyl chloride (PVC) is a non -crystalline plastic and raw material transparent.
The main performance is as follows
1. By adding plasticizers to make the material’s soft and hardness range.
2. Difficult self -extinguishing and poor thermal stability.
3. PVC is dissolved in ethyragone, hydrogen sutu, dichloroethane, and soft glue oil water (including ethyragone) for soft glue.
4. PVC is mainly used for enamel (and as a doll).
The molding process of polyvinyl chloride (PVC) understands
1. Soft PVC contraction rate (1.0 ~~ 2.5%) PVC polarity molecules are easy to absorb water, dry before forming, dry temperature 85 ~~ 95 ° C, 2 hours.
2. During the formation, the tube has been heated for a long time, and the chlorine chloride monomer and HCL (that is, degradation) are decomposed, so the dead corners of the mold cavity and the head of the head should be often cleaned.
3. Add ABS to soft PVC to improve toughness, hardness and mechanical strength.
4. Because the machining temperature of PVC is close to the decomposition temperature, the tube temperature should be strictly controlled, and the molding temperature should be used as low as possible. At the same time, the molding cycle should be shortened at the same time to reduce the residence time of the soluble in the tube. The temperature parameters of the tube, the front barrel 160 ~~~ 170 ° C mid -tube 160 ~ 165 ° C rear cylinder 140 ~~ 150 ° C.
5. For easy decomposition, poor liquidity, the mold runways and ports are as short as possible, thick to reduce the loss of less pressure and the as soon as possible, the cavity -type cavity injection pressure MPA should use high pressure and low temperature injection, back pressure 0.5 ~~ 1.5MPa, PVC products wall wall The thickness should not be too thin, and it should be above 1.5mm, otherwise it is difficult to charge the cavity.
6. The injection speed should not be too fast, so as to avoid strenuous friction when the solution is poured, so that the temperature will rise, and it is easy to cause shrinkage marks.
7. The mold temperature is as low as possible (about 30 ~~~ 45 ° C) to shorten the molding cycle and prevent the formation of the formation of the formation (the time the glue must be fixed by the format).
8. In order to prevent cold materials from blocking the mouth or inflowing into the mold cavity, a large cold material shaft should be designed.
seven. Polytealdehyde (POM Steel)
The formaldehyde (POM) is commonly known as Cymbicon Crystal Plastics. The main performance is as follows:
1. Polytealdehyde is a milky white and shiny plastic.
2. It has comprehensive mechanical properties, high hardness rigidity, good impact resistance, and excellent abrasion resistance and self -lubrication.
3. Organic solvents have good performance and stable performance.
4. After molding, the size is relatively stable and the temperature environment is less affected.
POM’s formaldehyde forming technology
1. Polytealdererdide hygroscopic (water absorption rate u003C0.5%) generally does not take a bath or a short bath before forming.
2. The molding temperature range is narrow, the thermal stability is poor, and the formaldehyde unit (darker of the melt color becomes darker) above 250 ° C. Therefore, it improves the temperature and the liquidity is harmful and invalid. Normal beer plastic should use lower tube temperature and short retention time, and improving injection pressure can improve the liquidity of the melt and the surface quality of the product. (Mel is more sensitive to cutting speed).
Temperature parameters: The front barrel 190-210 ℃ Middle tube 180-205 ℃ The tube 150-170 ℃.
Press the pressure parameters: The injection pressure is about 100MPa, and the back pressure is 0.5MPa.
3. Mold temperature: 80-100 ° C is appropriate (generally air transport oil).
4. The POM cooling contraction rate is very large (2 ~~ 2.5%). It is easy to reduce the shrinkage of beer plastic.
eight, polyethylene (PE) “flower material”
The polyethylene (PE) commonly known as “flower material” is crystalline plastic. The main properties are as follows:
1. The polyethylene is divided into two types: high -density (HPPE) sub -density (HPPE) and low -degree (LPPE), which weakens as the density is high and transparent.
2. Polyethylene is a translucent particle, and the appearance of the glue is milky.
3. Polyethylene has softness, impact resistance, extension and abrasion resistance, and low temperature toughness.
4. It does not melt at any melt at room temperature, and the chemical performance is stable and PE is difficult to bond.
5. The mechanical strength is not high, the thermal deformation temperature is low, and the surface is easy to scratch.
6. Polyethylene (PE) is often used for blowing plastic products.
The formation process of polyethylene
1. Good liquidity, a wide range of molding temperature, and easy to mold.
2. Injecting pressure and pressure should not be too high, avoiding large stress in the beer parts and causing deformation and cracking, the injection pressure is 60 ~~ 70MPa.
3. Dry treatment is not required before water absorption.
4. The temperature and quality of the tube is improved, but the molding rate of molding (2 ~~ 2.5%) The temperature of the barrel is too low to deform (more severe pouring out of the mouth, use multiple points to improve the warp), the temperature parameters of the temperature, and the temperature parameters : 200 ~ 220 ° C in front of the leaflet, 180 ~~ 190 ° C in the middle grip, 160 ~~ 170 ° C in the rear cylinder.
5. The front and rear mold temperatures are consistent (the mold temperature is generally 20 ~~ 40 ° C is suitable) cooling water should not be too close to the surface of the cavity, so as not to avoid the local temperature difference, so that the product residues internal stress. Improve the mold temperature, good product gloss, but long molding cycle. Reduce mold temperature, product softness and high transparency, high impact strength, too low and cold, causing product deformation or molecular orientation, in short, the hardness and flexibility of the product can be adjusted by adjusting the mode temperature.
6. Because the quality is soft, it is forcibly demolished without row (slider) when it is necessary.
. The polycarbonate (PC) (the most expensive)
Carbonate (PC) is commonly known as “bulletproof glass glue”. The appearance is transparent, the rigid is tough, the combustion is slow, and the fire is off after the fire.
2. PC material impact is the best in plastic.
3. The molding rate (0.5 ~~ 0.7%) has a high accuracy and high size stability.
4. Chemical stability is good, but it is not resistant to alkali, ketone, aromatic hydrocarbons and other organic melts.
5. Fatigue resistance is sensitive to gaps.
Carbonate (PC) molding process
1. PC is very sensitive to micro water. Before molding, the water content should be fully dry at 0.015%drying temperature 110 ~~ 120 ° C and 12HRS.
2. Poor liquidity and high pressure injection molding, but the injection molding pressure is too high, which will cause the product to remain large internal stress, and it is easy to crack
3. The viscosity of PC is very sensitive to temperature, and the temperature viscosity decreases. The front cylinder is 240 ~~ 260 ° C, 260 ~~ 280 ° C, and the rear cylinder 220 ~~~ 230 ° C does not exceed 310 ° C.
4. Mold design requirements
This rumors, flowing channel polishing, cavity and stamens should quench or hard chromium.
5. The injection speed is too fast, the solubility is easy to break, the pouring mouth is vague, and the exhaust (difficulty) burns the product.
6. Modern temperature 80 ~~ 100 ° C.
7. Under annealing treatment, 125 ~~ 135 ° C 2HRS, naturally cooling to room temperature.
Ten, polyamide (PA) nylon material
The polyamide is commonly known as “nylon” (Nylon), which belongs to crystalline plastics, such as nylon 6, nylon 66, nylon 1010 and so on.
1. Nylon has good toughness, abrasion resistance, durability, self -lubricating and self -extinguishing.
2. Good low temperature performance, high impact strength, and high tensile strength, good elasticity.
3. The nylon water absorption is large, and the tensile strength is increased to a certain extent after absorbing, but the contraction rate of other intensity (such as stretching, stiffness) is 0.8 ~~ 1.4%.
4. For weak acid, weak alkali and general solvents, the saturated methanol solution can also be dissolved in phenols (phenols can be used as adhesives) at normal temperature.
Newy molding process
1. Before injection, it needs to be fully dry. The drying temperature is 80 ~~ 90 ° C, and the drying time is 24HRS.
2. Nylonic viscosity, good liquidity, and prone to the pressure (flying edge) pressure is not too high, generally 60 ~~ 90MPa.
3. With the temperature of the barrel, the contraction rate fluctuates and highly fluctuated. The nylon material below the melting temperature is very stingy, which will damage the loop mold and screw. The temperature of the tube is generally 220 ~~ 250 ° C, and it should not exceed 300 ° C.
4. Mode temperature control:
Nylon is a crystalline plastic, and the product is highly affected by the mold temperature.
Themore temperature: Large crystallinity, rigidity, and abrasion resistance increases less.
This temperature is low: good flexibility, high elongation rate, small contraction rate, and the mold temperature is controlled at 20 ~~ 90 ° C.
5. High -speed injection:
This nylon melting point is high and the solidification point is high (fast molding, high production efficiency) is a smooth charging mold (do not reduce the melt to the melting point). The product dragon is thicker or overflowing with the thickness of the product.
6. Antuction treatment and temperature adjustment.
a annealing treatment: After the annealing, the crystallization can increase, the rigidity increases, it is not easy to deform and crack.
b temperature adjustment processing: maintain stable size, which is good for improving the toughness and improvement of the internal stress distribution. Temperature adjustment method: immerse boiled water or potassium acetate solution. Potassium: water = 1.25: 100 time 2 ~~ 16HRS.
The polyethylene acrylic (PMMA)
MAA “Agree”, which is organic glass, is a non -crystalline plastic
1. High transparency, light quality is not easy to deform, good light guide.
2. PMMA is difficult to get angry and can burn slowly.
3. Inflictter -resistant, powerful alkali, can be dissolved in aromatic hydrocarbons and chlorine chloride (methane can be used as adhesive).
4. Easy to mold and stable size.
5. The impact resistance and surface hardness are slightly worse, and it is easy to control the flowers, so it has higher requirements for packaging.
PMM for molding process:
1. Aga Li’s transparency is high, beer plastic defects such as bubbles, flow patterns, impurities black spots, silver wires, etc. are obviously exposed, so the difficulty of forming difficulty high products is low
2. The raw materials are fully dry, the drying of silver silk air bubbles, etc. Drying conditions: Temperature 95 ~~~ 100 ° C 6HRS material layer thickness does not exceed 30mm, and the fight should continue to keep warm to avoid re -blowing.
3. The liquidity is poor, it should be formed at high pressure, the injection pressure is 80 ~~ 100MPa. The pressure preservation pressure is about 80%of the injection pressure, and the back pressure should not be high to prevent early cooling of the flowing track.
4. The injection speed
The injection speed has a great impact on viscosity. Do not be too fast. If the injection speed is too high, it will cause plastic foam, burnt, and poor transparency. If the injection pressure is too low, it will make the product’s solid line thicker.
5. The material temperature
The liquidity increases with the temperature of the tube, but under the premise of being able to fill the cavity, the temperature should not be too high to reduce color change, silver wire and other defects, the front cylinder is 200 ~~~ 230 ° C, 215 ~~ 235 ° C, and rear pipes 140 ~~~ 160 ° C.
6. High mold temperature, high product transparency, and reducing poor fusion, especially reducing the internal stress of the product, and easy to fill the cavity, the mold temperature is generally 70 ~~ 90 ° C.
7. The design of the mold should be brief, smooth, and the wide pouring mouth is formed.
8. Reduce the internal stress
The thermal treatment temperature of 70 ~~ 80 ° C, hot air or water cold time is generally 4HRS.
9. Reduce beer and plastic black spots
a to ensure clean raw materials (environmental cleaning).
B cleaning mold.
C machine cleaning (the front end of the cleaning tube, screw, nozzle).
10. The mold surface is kept clean, and the plating is used to resist corrosion. Try not to use the mold as little as possible to increase the mold slope of the mold and facilitate the molding.
The four categories of commonly used plastic handboards
because the products produced by the enterprises are different every day, the handbued models needed to be made are different. The following:
1. ABS handboard models are generally widely used in product shells, and they are relatively integrated. Most of them are used in metal plated products, such as hydraulugulaton, vacuum steaming electrical plating, and the models of their materials have round sticks , Board, etc.
2. PMMA is an acrylic, also an organic glass. It has good transparency and is the best material for the production of transparent products. It is used for products with strong solubility, but its stronghold is relatively crispy. And it is suitable for institutions with cardiac hooks.
3. PP is a translucent material. Its advantage is that it is very resistant to impact, strong impact resistance, and it is also very flexible to belong to it. Products, such as car accessories, packaged as a folding handboard model.
4. PC is a product with good strength, high flexibility, and very good transparency. His advantages are set. In addition, it also adds glass fiber to improve steel and heat resistance. The plate materials are more suitable for Lens. The first choice and production of fine products requires the handboard model of production products that still maintain steel in high temperature environments.