Effect of different proportions of PVC and CPE on the performance of dry mix
release date: Source: China Plastics browse times: 64 put in the test piece 77 copyright and disclaimer
core tips: [China Packaging News] hs-1300 PVC resin is a general resin with medium and high molecular weight, which has large and uniform pores, narrow particle size distribution and fast absorption of plasticizer, Widely used in calendering or extrusion
[China Packaging News] hs-1300 PVC resin is a general resin with medium and high molecular weight. Its pores are large and uniform, particle size distribution is narrow, and plasticizer absorption is fast. It is widely used in calendering or extrusion to produce soft rubber film, artificial leather, cable, pipe material, soft profile, etc. it can also be used in the production of injection molded products
chlorinated polyethylene (CPE) is a random chlorinated polymer prepared from polyethylene (PE) through chlorination reaction. It has excellent weather resistance, heat aging resistance, oil resistance, chemical resistance, cold resistance, flame retardancy, bending cracking resistance and other characteristics. It is widely used in the impact modification of PVC products, and produces roof waterproof coiled materials, mining flame retardant conveyor belts, magnetic rubber, wires and cables, oil and acid transmission rubber pipes, etc. With the continuous development of the application field of CPE modified PVC products, CPE will be used more and more widely
in the PV industry, the requirements for automobile lightweight, low fuel consumption, low cost, low pollution, high safety and high comfort are becoming more and more stringent. In the extrusion processing of C soft sheet, some processes require CPE to be added in a certain proportion to improve the tensile strength and elongation at break of products, so as to produce the required products. In this paper, the effects of different dosage ratios of PVC and CPE on the properties of the dry mixture prepared under the same basic formula are discussed
1 test purpose
by changing the dosage ratio of PVC and CPE, carry out the tensile contrast test of non vulcanized sheets, and observe the change law of tensile strength and elongation at break
2 experimental formula
2.1 formulation
on the basis of the same formula, the dosage of PVC and CPE is adjusted. There are a total of 8 experimental formulas, and the experimental formulas are shown in Table 1 (mass fraction)
2.2 formula description
pvc and CPE are both produced by Qingdao Haijing Chemical Group Co., Ltd. the PVC brand is hs-1300, and the CPE brand is cpe135a; CaCO is colloidal CaCO produced by Zilong chemical plant in Zhangdian, Zibo
dop is analytical pure; The stabilizer is a rare earth stabilizer produced by a factory in Laoshan, Qingdao. With the increase of formula number, the dosage of PVC gradually decreases and the dosage of CPE gradually increases, but the total amount of both is still 100 phr
3 test instrument
shr-10a high speed mixer, Zhangjiagang happy Machinery Factory; Sk-160b open plasticizer, Shanghai Machinery Factory; Cmt-302 electronic universal testing machine, Zhuhai Sansi Measuring Instrument Co., Ltd; Shore LX-A rubber hardness tester, Jiangdu testing machinery factory; The thickness gauge, with an accuracy of 0.01 mm and a measuring range of 0 ~ 10 mm, is a test factory of the standard measurement management institute of Shanghai Light Industry Bureau
4 test process
4.1 mixing
weigh the raw materials according to the formula, add the weighed powder into the mixing chamber of the high-speed mixer, and mix the materials at high speed. After 3 ~ 5rain, the powder in the mixing chamber is basically mixed evenly; While stirring at high speed, DOP is added from the small feeding port. When the material temperature reaches 100 ℃, the material can be discharged and cooled for standby
4.2 preparation of test piece
4.2.1 tablet refining
raise the roller temperature of the double roll open mill to 150 oC and keep the constant temperature for 30min. Adjust the roll distance of the roller to the minimum, and then pour 400 g of dry mixture between the two rollers to start timing. After the rubber is wrapped by the roller, cut the rubber and make a triangle bag for uniform mixing. After mixing for 3 minutes, make a triangle bag for blanking and standby. The remaining 7 samples were mixed in this way
4.2.2 unloading
adjust the roll distance between the rollers to be slightly smaller than the thickness of the unloading. Put the unloading triangle between the two rollers for tablet pressing, and then unload the tablet for standby after the thickness is uniform
4.2.3 cutting
place the film for more than 2 hours, and cut it after the film is homogenized. Use a cutting machine with a cutting knife width of 6 mm and a length of 25 mm to cut along the direction of the next piece
4.3 test standard
hardness shall be tested according to gb/t 531-1999~ indentation hardness test method of rubber pocket durometer; Tensile strength, According to gb/t528-1998 {determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber "; the elongation at break is converted by the instrument measuring tensile strength through tensile strength.
4.4 test results
first measure the shore a hardness and thickness of the test piece, and then cut three standard test pieces from each test piece for parallel tensile test. The test results are shown in Table 2, figure 1 ~ Figure 3.
4.5 test data analysis
4.5.1 hardness
With the increase of CPE dosage, the hardness showed a downward trend. When the CPE dosage was more than 40 phr, the hardness decreased sharply
4.5.2 elongation at break
with the increase of CPE dosage, the elongation at break increased sharply, from 32.19% of 0 parts to 700.86% of 100 parts
4.5.3 tensile strength
when the dosage of CPE is less than 60 phr, the tensile strength decreases sharply; When the amount of CPE is equal to 6 (), the tensile strength decreases to the lowest; When the dosage of CPE is 60 ~ 80 phr, the tensile strength index has almost no change; When the content of CPE is more than 80 phr, the tensile strength increases slightly. It can be seen that when m (PVC):m (CPE) 1:1, increasing the amount of CPE has little effect on the tensile strength
4.5.4 plasticizing performance
during the test, the author found that the roll wrapping performance of Formula 1 and 2 was poor, and the roll wrapping performance of formula 3 ~ 8 gradually improved. This shows that with the increase of CPE dosage, the plasticizing performance of the formulation system increases
from the test results, it can be seen that with the gradual increase of CPE dosage, the plasticization performance of the dry mix improves, the hardness decreases, the elongation at break increases, and the tensile strength shows an overall downward trend. Increasing the amount of CPE can make the products have certain rubber properties on the basis of plastic properties, which can greatly improve the toughness of products. Through experiments, PVC processing enterprises can find a suitable entry point from the influence law of PVC and CPE dosage ratio on performance, so as to produce PVC products that meet the needs
LINK
Copyright © 2011 JIN SHI