PVB: a variety of high-performance materials, and its downstream applications continue to expand
Polyvinyl butyral (PVB), which is formed by condensation of Polyvinyl Alcohol (PVA) and butyraldehyde, is the main variety of polyvinyl acetal products that have been industrialized at present. Pvb Resin and Plasticizer triethylene glycol diisooctanoate (3GO) or di-n-hexyl adipate (DHA) can be mixed, plasticized, extruded and cast to obtain PVB film materials (i.e. PVB intermediate film or PVB film), which are mainly used in the fields of building laminated glass, automobile front bumper safety glass, photovoltaic packaging adhesive film and so on.
Because PVB has excellent adhesion with glass, metal and ceramics, and has excellent properties such as high transparency, weather resistance, impact resistance, non toxicity and non corrosiveness, PVB film has been an excellent sandwich material in the field of safety glass such as architecture and automobile since its inception in the 1930s. In recent years, the application field of PVB is still expanding. High performance products are in photovoltaic packaging adhesive film Bulletproof glass and aerospace materials continue to penetrate.
Due to the strong adhesion of PVB, the glass fragments of building laminated glass and automobile front windshield can still firmly adhere to the PVB film after self explosion or external force crushing, which can greatly reduce the safety threat of glass fragments falling from high altitude or impact crushing. In addition, the PVB interlayer has excellent impact resistance. Its multi-layer structure or special PVB laminated glass can resist the penetration of bullets and has excellent safety performance. In addition, according to the PVB product manual of Changchun chemical industry, under the same test environment, PVB laminated glass is also significantly ahead of ordinary glass in terms of UV isolation ability and sound insulation effect. PVB laminated glass also has the advantages of heat insulation and energy saving, color change and dimming, non-toxic and environmental protection.
According to markets and markets, in 2019, the global PVB market scale was about US $3.1 billion, and the CAGR (2009-19) reached 6.7%. It is estimated that it will reach US $4.4 billion in 2024 (about 7.3% in 20-24 years). It mainly benefited from the increased demand of emerging markets such as Asia Pacific and the application penetration of automotive high-grade glass, photovoltaic and protective glass. According to mordorintelligence, in the global PVB downstream applications in 2021, the automobile and construction sectors accounted for nearly 90% in total. In terms of the consumer market, according to the data of zhongyan.com, the consumption in Asia Pacific, Europe and North America accounted for about 40%/28%/25% respectively in 2019. Domestically, according to cnr.com, the domestic PVB market scale will be about 8 billion yuan in 2020, which is expected to reach about 12.1 billion yuan in 25 years, and the CAGR will reach 9% in 21-25 years, mainly benefiting from the improvement of building safety and energy saving requirements, as well as the demand growth under the continuous penetration of applications in automotive and photovoltaic fields.
In terms of laminated glass in buildings, according to the regulations on the administration of building safety glass, safety glass must be used in domestic buildings with 7 floors and above, window glass with an area of more than 1.5m2 or floor to ceiling windows whose bottom edge is less than 500mm from the final decoration surface, curtain walls, parts vulnerable to impact and impact and other parts that need glass as building materials; The opinions on promoting the structural adjustment of flat glass industry issued by the national development and Reform Commission requires "continuously increasing the proportion of self-use deep-processing glass and promoting the promotion and application of energy-saving glass products and glass for solar energy industry". Under the continuous development of the construction industry and policy guidance, the application market of green and energy-saving glass products in China is expected to continue to expand, while PVB laminated glass is expected to expand due to its safety, energy conservation, sound insulation With the advantages of environmental protection, the demand is expected to continue to grow.
According to the data of the National Bureau of statistics, the domestic laminated glass output was 132 million square meters in 21 years, a year-on-year increase of + 15%, and the CAGR in 17-21 years was about 8%. In recent years, it has maintained an overall growth trend. According to the report on issuing shares to purchase assets and supporting raised funds and related party transactions (Draft) (Revised) (March 18, 2022) of wanwei hi tech, the demand for PVB film per square meter of laminated glass is about 1.22kg. Considering the relative downturn in construction, real estate and other industries since 22 years, the downstream demand of laminated glass may slow down, so it is assumed that the compound growth rate of domestic laminated glass production in 22-25 years is 5%, It is estimated that the demand for PVB film in the field of building laminated glass will reach about 195000 tons by the end of 25 years, an increase of about 55000 tons compared with the end of 20 years.
The demand for PVB film in the field of automotive glass comes from the glass replacement demand of existing vehicles and the installation demand of new vehicles. According to the data of the National Bureau of statistics, the domestic car ownership and car output in 21 years were about 302 million and 26.28 million respectively, with a year-on-year increase of 7.5% and 3.8% respectively. According to the report on issuing shares to purchase assets and supporting raised funds and related party transactions (Draft) (Revised) (March 18, 2022) of wanwei hi tech, at present, the safety performance of automobile front windshield is higher, and PVB film is mostly used in the field of front windshield. The demand for PVB film for front windshield of each vehicle is about 1.021 tons. If the compound growth rate of automobile ownership / output in 22-25 years is 4.5%, It is estimated that the annual replacement rate of the front bumper of the retained vehicle is 5%. By 25 years, the demand for PVB film in the domestic automotive field will be about 59000 tons, an increase of about 20000 tons compared with the end of the 20th year.
PVB is expected to gradually penetrate into the field of photovoltaic packaging adhesive film, and the application in the field of BIPV may be the first breakthrough
The long-term reliability of photovoltaic modules is greatly affected by module packaging. The primary performance of ideal module packaging materials is the adhesion with glass modules. Other properties require strong water permeability, good weather resistance, long service life, high transparency, sufficient mechanical deformation, etc. At present, the main packaging materials of photovoltaic modules are EVA adhesive film and Poe adhesive film. EVA adhesive film is the most widely used because of its advantages of high transparency, low melting point and easy processing. However, it has some problems, such as weak water permeability, poor weather resistance and short service life. In recent years, the penetration rate of products with better performance such as Poe adhesive film (including coextrusion) has gradually increased. According to CPIA, the use proportion of transparent EVA adhesive film in China has decreased to about 52% in 21 years, It is expected to continue to decline in the future, and the penetration rate of products with better performance such as POE / EPE is expected to continue to increase, which is expected to reach more than 25% in 25 years.
From the perspective of photovoltaic module types, the traditional single glass modules will have problems such as snail pattern and PID attenuation after being put into use for several years, and the power generation efficiency will decline significantly. With the advantages of higher power generation efficiency, reliability and durability, the use proportion of double glass modules has gradually increased in recent years, and it is expected to continue to penetrate in the future. According to CPIA, the proportion of domestic double-sided photovoltaic modules is expected to reach about 70% in 25 years.
As a packaging material, PVB intermediate membrane is mainly used in the field of double glass (one side of the traditional single-sided module is the frame, and PVB packaging is mainly based on the double-sided pressing process). At present, PVB is still used in a small proportion due to the high production barrier and high packaging cost of photovoltaic products. However, with its excellent properties such as high adhesion, high water permeability resistance and high weather resistance, it is expected to gradually attract attention with the increase of the application of double-sided modules. Specifically:
1) Performance advantages of PVB adhesive film. According to cecep's PVB double glass components and mass production solution (October 2017), under the same test conditions, the water permeability of PVB components is much better than Poe and EVA (the water permeability thickness of PVB film is 0mm under the condition of 121 ℃ temperature and 100% humidity and 192h test time, while the water permeability width of Poe and EVA is 10mm and 30mm respectively), and the performance of PVB membrane in ACID, alkali and salt spray resistance The high temperature resistance and impact resistance test are significantly better than Poe and EVA. The good weather resistance and extreme environmental resistance also make the service life of PVB film expected to be significantly longer than EVA and POE (refer to the traditional building grade PVB film, the service life can reach 50 years or more).
The reason why PVB adhesive film shows extremely strong water permeability resistance is that during the bonding process between PVB and glass, the hydroxyl group in the adhesive film (from the vinyl alcohol chain segment in the molecule) can form a solid hydrogen bond with the oxygen atom in the glass, so that the hydrophilic group on the interface disappears and the water vapor is difficult to penetrate. However, Poe (or EVA) usually needs to use coupling additives in the processing process to realize the connection between the adhesive film and glass, However, the relatively loose connection of coupling agents leads to lower interfacial bond energy and easier water vapor penetration.
2) PVB processing equipment. The complexity of processing technology and the lack of equipment are one of the important factors restricting the application of PVB adhesive film in the field of photovoltaic packaging components. The traditional EVA and Poe adhesive film can be encapsulated by lamination, while the PVB adhesive film is difficult to achieve effective adhesion with glass through the traditional lamination process. Generally, it needs to be processed with autoclave or roller / high-pressure combination process, In the early stage, there has been no significant breakthrough in processing equipment and processes in China.
In recent years, with the increasing requirements of downstream users for PID resistance, service life and power generation efficiency of modules, some domestic enterprises have begun to increase the exploration of the application of PVB double glass modules. According to destai's application of photovoltaic PVB film on double glass modules (January 2017), the PVB double glass processing technology they independently explored has been gradually popularized and applied, Relying on the supporting roller press and autoclave equipment, the batch processing of PVB double glass components can be realized, and the efficiency is improved compared with the traditional lamination process. The company's double glass components have been popularized and applied in 20MW projects in Hanchuan, Hubei, Leping, Jiangxi and Linyi, Shandong respectively. We believe that with the accumulation of industry enterprises' investment in the packaging and application of PVB double glass components, the barriers of processing equipment and technology are expected to be further broken through in the future.
3) PVB material availability. With the rapid development of photovoltaic industry, the domestic demand for EVA and Poe has been increasing in recent years, and the production barriers of EVA particles and Poe particles used in photovoltaic packaging field are also high. According to Baichuan Yingfu, in the past 21 years, the domestic EVA output was about 990000 tons, while the apparent consumption was about 2.04 million tons, with an import dependence of 55%. Moreover, only a few enterprises such as sierbang petrochemical, Lianhong Xinke and Ningbo Formosa Plastics can produce photovoltaic products, which still need to rely on imports; In terms of Poe, at present, the global production capacity is monopolized by foreign giants such as Dow Chemical and Mitsui chemical. According to China chemical information, domestic Poe will still mainly rely on imports in 2021.
With the production capacity of about 110000 tons of PV Materials from Sinochem and Sinochem, Sinochem has begun to realize self-sufficiency in domestic PV materials, including Sinochem, Sinochem, etc., but Sinochem has begun to produce about 110000 tons of PV materials. Therefore, by comprehensively comparing the localization stage and product performance advantages of EVA, Poe and PVB materials (photovoltaic grade), PVB materials will accelerate to catch up and gradually replace part of the market share of EVA and Poe in the future, or they are still in a good window period.
4) Application fields. The main application advantage of PVB adhesive film lies in the field of double glass modules. We believe that combined with the process characteristics of PVB module packaging and its application form in the field of architectural laminated glass, its application in the field of distributed photovoltaic may open up space earlier. With reference to the report "special topic of building energy efficiency: spring tide of thin film BIPV" released by Huatai research on April 6, 2022, for new buildings, BIPV mode is expected to become the main form of building photovoltaic in the future. According to the data of the National Bureau of statistics, the installed capacity of domestic centralized / distributed PV was about 200 / 108gw respectively in 21 years, and the proportion of distributed PV has increased to about 35%. According to the data of Becquerel Institute, the installed capacity of domestic BIPV in 2018 was only about 0.1gw, which is still far lower than that of developed countries and regions such as Japan, France, Italy and North America. The development potential of domestic BIPV is outstanding.
Referring to the prediction of the Research Report "the top-level design is finalized and the carbon peak target can be reached" issued by Huatai research on November 7, 2021, the new installed capacity of domestic BIPV is expected to reach about 107gw by 2025. According to CPIA data, each GW of photovoltaic installed capacity consumes about 100 million square meters of photovoltaic adhesive film; The unit mass of PVB membrane is calculated as 1.22kg/m2 (refer to the data of wanwei's report on issuing shares to purchase assets and supporting raised funds and related party transactions (Draft) (Revised) (March 18, 2022); Considering that the short-term PVB adhesive film packaging equipment and technology are still in the iterative upgrading stage, we assume that 21-23 years are in the early stage of application penetration, 0.2% / 0.5% / 1.0% respectively, while 24-25 years may be expected to usher in a rapid breakthrough, and the penetration rate will accelerate slightly, 3.0% / 5.0% respectively. Therefore, it is estimated that the demand for photovoltaic grade PVB film will reach 65000 tons in 25 years.
PVB high-end categories usher in the opportunity of domestic substitution, and enterprises integrating the industrial chain are expected to benefit
According to China chemical information, in 2020, the global PVB production capacity was about 800000 tons, of which the annual production capacity of American shounuo company was about 110000 tons. It is the world's largest PVB production enterprise. At present, the market share of high-end categories in the fields of global construction grade, automobile grade and photovoltaic grade is mainly monopolized by four enterprises, namely American shounuo company, Japanese Ponzi chemical, American DuPont and Japanese cola. With the advantages of technology and product performance, overseas enterprises usually sell PVB membrane at a higher price than domestic enterprises. According to the data in the report on issuing shares to purchase assets and supporting raised funds and related party transactions (Draft) (Revised) (March 18, 2022) issued by zhongyan.com and wanwei hi tech, the average price of the high-end category of construction grade PVB membrane of shounuo / Shuishui chemical in 20 / 21 was about 45000 yuan / ton, while wanwei wusheng construction grade The overall price of automobile grade products is 20000-30000 yuan / ton. Domestic enterprises still have great room for technology improvement and product quality improvement in the field of high-performance PVB membrane.
According to China chemical information, the domestic production capacity of PVB in 20 years is about 110000 tons, but the production enterprises are relatively scattered. According to destai's prospectus, most domestic enterprises still use recycled materials to produce PVB intermediate membrane, which is of low quality. As a whole, it is mainly in the middle and low-end markets such as building laminated glass, and there are few enterprises supporting the production capacity of PVB Resin and intermediate membrane. In recent years, domestic enterprises, including wanwei hi tech (wanwei Wansheng to be acquired has the production capacity of automobile grade PVB film), destai (has the production capacity of automobile grade and photovoltaic grade PVB film), Hong Kong Jiantao group, etc., have gradually increased their market share in the field of PVB through continuous improvement and process, and the localization degree of PVB is expected to be further improved in the future driven by downstream demand.
From the perspective of industrial chain matching, PVA Resin is the basic resin material required for PVB production. Referring to the prospectus of destai, the average cost of PVA accounts for about 24% of the production cost of PVB in 16-18 years, and the average unit consumption is about 0.49 T / T respectively. According to our calculation, the demand for PVB in the field of building laminated glass / automotive safety glass / photovoltaic BIPV modules is expected to reach 19.5/5.9/65000 tons respectively by 25 years. Therefore, based on the unit consumption of 0.49 T / T PVA, the demand for PVA in the domestic PVB field is expected to reach 156000 tons by 25 years, an increase of about 56000 tons compared with the end of 21 years.
Referring to the report "PVA dust settled, downstream of the power industry chain" released by Huatai research on March 29, 22, after long-term competition and optimization, the supply pattern of PVA industry has been basically stable in recent years. The total domestic production capacity has been stable at 830000 tons since 2019 (excluding the 120000 ton unit of Taiwan Changchun group, which is less involved in the domestic market, and the 46000 ton unit of Shanghai Petrochemical and chemical division, which is partially operated throughout the year), The stock of 4 enterprises (7 units) and their respective production capacity have not changed.
According to Baichuan Yingfu, the total domestic consumption + export of PVA in 21 years is about 700000 tons, and the operating rate of the industry has been at a high level. Considering the demand driven by PVB and other downstream fields (such as PVA optical film), if the PVA competition pattern maintains the current state in the next few years, the PVA market supply may be tight as a whole. Therefore, we believe that if PVB enterprises have PVA integrated supporting capacity, they are expected to have long-term competitiveness, The stock PVA enterprises are also expected to continue to benefit from the promotion of PVA prosperity driven by the demand in PVB and other fields and after the optimization of industry structure. At present, in terms of domestic listed enterprises, wanwei hi tech has pva-pvb integrated supporting capacity; Hong Kong Jiantao group and Dongcai technology have the capacity of PVB resin and film, but the two enterprises have not yet extended to the field of PVA.
