PVC door and window profile
DATE：2022/3/25 8:46:29 / READ： / SOURCE：This station
PVC door and window profile
1. Material selection and formula design(1) raw material PVC has five kinds of polymerization methods: solution, bulk, suspension, emulsion and micro suspension. Suspension PVC resin is very suitable for the manufacture of PVC hard products. The surface of loose resin is loose and has pores. The specific surface area is 8 times larger than that of compact resin, which is conducive to the absorption of various additives. Breathable membrane production line www.handern.com com
PVC resins with different relative molecular weights have different physical properties and processing properties. Generally, the greater the relative molecular weight, the better its physical and mechanical properties; But at the same time, the greater the relative molecular weight Its viscosity is also large, the more difficult it is to process and shape. It is necessary to consider the requirements of R-PVC as a building material for various mechanical properties, such as wind pressure resistance and certain building strength, as well as the molding and processing characteristics of special-shaped materials, such as bars and grooves are not easy to fill, and resin fluidity is required. Therefore, it is determined to select the suspension loose resin with K value of 65 ~ 70, and the corresponding domestic resin is pvcsg-5.
Additives are as follows: breathable membrane production line www.handern.com com
① Heat stabilizer. PVC is a heat sensitive polymer, which is easy to decompose when heated during processing and use. Lead stabilizer with strong stability and low price is selected as the main stabilizer and metal soap as the auxiliary stabilizer, which has synergistic effect.
② Modifier. PVC plastic has the weakness of low-temperature embrittlement, which greatly restricts the plastic steel doors and windows. The popularization and application of low-temperature impact modifier in cold areas has solved this problem. ENA ACR. CPE has long production time and stable quality. CE with 36% chlorine content is most suitable for the divine attack modifier of PC to overcome the shortcomings of high precision and difficult processing of PVC. At the same time, the working mechanism of acrylic copolymer is also used Breathable membrane production line www.handern.com com
③ Light stabilizer. PVC profiles as doors and windows are directly exposed to the hot sun, wind and rain, so the weather resistance of profiles is very important. The high-energy ultraviolet in sunlight has the greatest impact on the degradation of PC. adding ultraviolet absorber in the formula can double the service life of doors and windows. Rutile titanium dioxide, as a colorant, has a good role in shielding ultraviolet and reflecting infrared light. Of course, the color of doors and windows can be adjusted according to the wishes of users, such as bronze and imitation aluminum alloy, but its weather resistance effect is worse.
④ Other additives. Due to processing reasons, internal and external lubricants are essential. Special attention should be paid to phase resistance, volatility and mobility in the selection of lubrication system. At the same time, CaCO; And other fillers should be controlled at an appropriate amount, which not only makes the profile easy to set, but also improves the dimensional stability. If the amount is too large, the strength will be significantly reduced and the profile is fragile. Therefore, CaCO; The dosage should not exceed 4 copies. Breathable membrane production line www.handern.com com
(2) To sum up, the formula (mass fraction) is as follows:
PVC SG-5 one hundred Two salt 2CPE 8~15 Metal soaps one point two Processing aids 3~4 lubricant appropriate amount CaCO, Ultraviolet absorber zero point five 4 three salts Colorant Appropriate amount 3
The profile formula has been successfully used in production in Beijing, Heilongjiang and other places. The products have been tested by the national chemical building materials testing center, and their performances have exceeded the national standards and reached the excellent level.
2. Production equipment
(1) Extrusion equipment the main equipment for profile production is plastic extruder. There are many kinds and models of extruders. PVC is a heat sensitive and shear sensitive polymer, which is difficult to process. Twin screw extruder is suitable for direct processing of powder, and the granulation process can be omitted. At present, the outward opposite conical twin-screw extruder is used. It has the following characteristics:
1. High heat transfer rate, which is conducive to the plasticization and transportation of materials; And the screw is not easy to break, so the bearing powder with large load capacity can be selected to prolong the service life of the extruder.
2) Small transmission area and shear rate of screw to melt; The end area is small. Under the same head pressure, it has a small axial pressure, which reduces the milk load of the thrust bearing. Therefore, the dimensional twin-screw extruder is especially suitable for directly extruding PVC profiles with powder. (2) Fixed production key of die profile. The vacuum cooling shaping die is especially suitable for the shaping of cavity profile with complex structure. The first mock exam has been developed for the first mock exam, and the four section of the auxiliary profile has been developed.
(3) In addition to the mixing equipment and main machine, the profile production equipment also includes tractor, cutting saw, unloading frame, water pump, air compressor, distribution box and refrigerator providing water, electricity and gas, crusher configured for recycling waste plastics, etc. of course, in order to ensure the quality, testing equipment is also essential. Breathable membrane production line www.handern.com com
3. Preparation process
(1) The production process flow of RPVC plastic profile is determined according to the structure, performance requirements and equipment of RPVC profile, as shown in the figure
PVC raw materials and additives - batching - mixing Extrusion molding cooling shaping
Storage tank Weighing system high heat cold mixing unit Extruder Vacuum setting die
tow Unloading aging treatment
Tractor cutting saw Flap table platform
Author：admin