Prices rose by more than 15%, and PVDF membranes for PV backsheets rose in the off-season
Apr 28, 2018
Recently, the price of PVDF membranes for photovoltaic backsheets has risen by 15 to 18% in the April low season of PV market demand.
In response, related PVDF membrane companies and backsheet companies stated: “The main reason for this price increase is due to the soaring prices of raw material R142b (1.8 parts of R142b to 1 part of PVDF) and the rapid growth of lithium battery industry (Lithium industry in 2017). With an increase of 34%, both demand for PVDF resin increase, resulting in a reduction in PVDF resin supply in the PV industry."
According to statistics, the purchase price of PVDF resin in the lithium battery industry is about twice that of the photovoltaic industry.
Since the Chinese government signed the "Montreal Protocol" to make a commitment to phase out the production and consumption of HCFCs, the phase-out will mainly focus on the R22, R141b and R142b products, and the domestic HCFCs quota production . Compared to 2013 production and consumption levels, China needs to phase out 35% by 2020 and eliminate all HCFC production and consumption by 2030.
Therefore, the quota production was affected by the factory under the influence of the national control policy. As a result, the supply of R142b on the market became increasingly tight. The ex-factory price of R142b was from 14,500 yuan/T in October 2017, and the execution price rose to 19,500 to 20,000 yuan/month in March 2018. T, up 34%, HF and R142b price changes are shown in Figure 2.
PVDF full name of polyvinylidene fluoride, is a white crystalline polymer, density 1.17 ~ 1.79g/cm3, melting point 172 °C, long-term use temperature 40 ~ 150 °C, decomposition temperature 316 °C. Due to the fact that PVDF resin contains a large number of CF bonds, and the order of the alternating fluorine-containing group and non-fluorine-containing group in the molecule, PVDF is superior in weatherability, corrosion resistance, high temperature resistance, and oxidation resistance. main reason:
Weatherability - PVDF has excellent weathering resistance, extremely resistant to UV and damp heat aging;
Flame retardancy - limiting oxygen index of 44%, self-extinguishing in air, flame retardant rating of UL94 V-0;
Chemical resistance - extremely resistant to corrosion by strong acids, alkalis and salt sprays;
Electrical performance - intramolecular dipole moment of 7 * 10-30C.m, is currently the most piezoelectric polymer found;
Mechanical Properties—PVDF is the highest mechanical strength fluororesin, and its tensile strength is 4 times that of PTFE.
In 1948, PVDF resin was first synthesized by T-FORD. PVDF resin was obtained by polymerization of vinylidene fluoride (VDF) monomer at a pressure of 30MPa or more and 20 to 250°C. The preparation of PVDF mainly includes emulsion polymerization and suspension polymerization.
At present, the global PVDF resin production capacity is about 50,000 tons, mainly distributed in Asia (60%), Europe (20%) and North America (20%). It is second only to PTFE, the second largest fluoroplastic, and has been widely used in industrial processes. The application (the main market distribution is shown in Figure 3).
With its excellent performance, huge supply, and low price compared with other fluorine materials, PVDF has undergone several years of development and has occupied a huge market share in the photovoltaic backsheet industry.
In addition to PVDF membrane (polyvinylidene fluoride), PVF membrane (polyvinyl fluoride), ETFE membrane (ethylene-tetrafluoroethylene copolymer), ECTFE membrane (ethylene-vinylidene fluoride copolymer), THV membrane (tetrafluoroethylene- Fluorinated materials such as hexafluoropropylene-vinylidene fluoride copolymer) are also very good weathering protection materials, and can fully meet the requirements for outdoor use for 25 years. However, due to the raw material supply capacity and cost reasons, it has not been applied to scale on photovoltaic backsheets. At present, only PVDF and PVF are widely used in the photovoltaic backsheet industry.
Among various materials, PVDF has become a mainstream photovoltaic backsheet weathering material in recent years due to its excellent processability, weatherability, barrier properties, and low commercialization costs.
It is expected that as the price of R142b continues to rise and the lithium battery industry grows rapidly, the price of PVDF film will continue to rise. Affected by this price trend, some companies started cutting corners to cut costs.
As the outermost protective material of the module, the PVDF film plays a decisive role in the long-term stable use of the module. Experts in the industry have called for not pursuing the pursuit of low-cost costs because of rising prices. Component manufacturers also need to consider comprehensively. The lifetime of PV modules is the first priority. PVDF membranes account for less than 1% of component costs, but the The service life is extremely important.
