Production process of PVB:

Currently,Polyvinyl Butyral Resin (PVB) is mostly produced using an extrusion casting method. China has made some high-end PVB in the past, especially for the military, like in aircraft and military vehicles, but there hasn’t really been a large-scale market for it.

Since the technology behind PVB is a closely guarded trade secret, we don’t have a clear public description of the process. Still, we can get a rough idea from technical documents:

1. First, the raw materials are fed into different extruders by the feeding system, and the pellets are evenly plasticized and molten in the extruder by heating;

2. The molten body passes through the filter to remove impurities;

3. The melted material flows out through the adjustable discharge port after removing the impurities until it cools down and takes shape as a film.

4. The film passes through the automatic X-ray measurement system to see if the thickness meets the technical requirements;

5. After the film goes through processing, it gets treated on the surface, trimmed, wound automatically, and cut into shape. At this point, it's ready as a final product.

For PVB film, it’s important that the surface is flat. If the film is 0.76mm thick, any thickness variation should be no more than 0.02mm. When measuring in both vertical and horizontal directions over a range of 50mm, the error should be under 0.006mm. Also, the moisture content has to stay below 0.3%, and the natural rating should be under 12%.

The technical difficulty of PVB production：

In terms of process, the ratio of polyvinyl butyral resin and plasticizer is one of the key points to determine the quality. In addition, since PVB has high requirements for humidity, special treatment is required during slitting, packaging, storage, and transportation;PVB needs specific humidity levels, so we have to be careful with slitting, packaging, storing, and transporting it. Plus, to make high-quality PVB, we need good resin, which means new projects will need extra resin production areas. This adds some new challenges for managing the process.

For PVB (such as Butvar B-74) in the solar industry, there are extra demands for resistivity and temperature compared to what’s needed for regular car glass or curtain walls. Usually, the resistance furnace requires more than 1000 ohms/cm2; the temperature must be lower than the tolerance temperature of the film to avoid damaging the reaction layer.

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Polyvinyl butyral resin (PVB) is a solvent-based resin synthesized by acetalization reaction of polyvinyl alcohol (PVA ) and butyraldehyde under the action of coal catalyst

• General characteristics

The appearance of PVB is white spherical porous particles or powder, and its specific gravity is 1:1; but the filling density is only 0.20~0.35g/ml.

• Thermal properties

The glass transition temperature (Tg) of PVB ranges from 50℃ for low overlap to 90℃ for high overlap; this glass transition temperature can also be adjusted to below 10℃ by adding an appropriate amount of plasticizer.

• Mechanical properties

PVB has excellent film-forming properties and gives the coating film quite good properties such as warp strength, tear strength, abrasion resistance, elasticity, flexibility, gloss, etc.; it is especially used in bonding safety glass interlayers, making the glass have strong impact resistance and penetration resistance, and it is still not replaced by other materials.

• Chemical properties

PVB coatings have good water resistance, resistance and oil resistance (resistance to aliphatic, mineral, animal and plant oils, but not castor oil). Because PVB contains high hydroxyl groups and has good dispersibility for pigments, it is widely used in printing inks and coatings. In addition, its chemical structure contains both hydrophobic acetal and acetate groups and hydrophilic hydroxyl groups, so PVB has good adhesion to glass, metal, plastic, leather and wood.

• Chemical Reaction Properties

Any chemical that can react with secondary alcohols will also react with PVB. In a lot of PVB applications, it's common to mix it with thermosetting resins. This helps to strengthen the hydroxyl groups in PVB, making it more resistant to chemicals, solvents, and water. Depending on the type of thermosetting resin and how much you mix with PVB, you can create coatings with different features like hardness, toughness, and impact resistance.

• Safety Properties

Pure PVB is non-toxic and harmless to the human body. In addition, ethyl acetate or alcohol can be used as solvents, so PVB is widely used in printing inks for food containers and plastic packaging in Europe and the United States.

• Storability Properties

As long as PVB is not in direct contact with water, it can be stored for two years without affecting its quality; PVB needs to be stored in a dry and cool place and avoid direct sunlight. Avoid heavy pressure when storing PVB.

• Solubility Properties

PVB dissolves in alcohol, ketones, esters, and some other solvents. The solubility in various solvents varies according to the functional group composition of PVB itself. Please refer to CCP PVB Solvent Solubility Table. Basically, alcohol solvents mix well, but methanol doesn’t blend as easily with substances that have a lot of acetal groups. The more acetal groups there are, the easier it is to mix with ketone and ester solvents. PVB has good solubility in alcohol ether solvents, like Cellosolve. It only partly mixes with aromatic solvents such as xylene and toluene, and it won’t mix at all with hydrocarbon solvents.

PVB (such as Changchun PVB) has good film-forming properties. The coating formed by PVB (Butvar B-72 & PVB WWW-A-20) has excellent properties such as high transparency, elasticity, toughness, strength resistance, oil resistance, flexibility and low-temperature impact resistance.

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N-Phenylmaleimide (abbreviated N-PMI), also known as monomaleimide,(C₁₀H₇NO₂, CAS 941-69-5) manufactured by Yangchen Tech used as a high-performance polymer synthetic monomer and modifier.  Structurally, N-PMI features a maleimide ring bonded to a phenyl group, making it highly reactive in both free-radical and ionic polymerizations.  It is produced as a pale yellow crystalline powder (melting point \~88–90 °C) and is valued for its ability to impart heat resistance, mechanical strength, and unique functional properties to resins and plastics.  N-PMI also exhibits photosensitivity and biocidal (disinfectant) activity, which has led to its use as a bactericide, fungicide, and antifouling agent in coatings.

Chemical and Functional Properties

Heat Resistance: N-Phenylmaleimide greatly improves thermal stability when copolymerized with vinyl monomers.  Even small additions (≈1–5% by weight) to ABS, PVC or PMMA resins can raise the heat distortion temperature (HDT) by \~2 °C per wt% of N-PMI.  For example, incorporating 10% N-PMI into ABS can elevate its heat-resistance to about 125–130 °C.  In comparative studies, N-PMI–modified ABS achieved HDT near 150 °C, whereas typical α-methylstyrene modifiers cap around 115 °C.  This high thermal stability makes N-PMI a preferred heat-resistant ABS modifier and engineering polymer additive.

Mechanical Properties: N-Phenylmaleimide enhances the mechanical strength and stiffness of polymers.  Copolymers containing N-PMI show higher tensile strength, hardness, and impact resistance than unmodified plastics.  It also improves melt-flow and processability, enabling easier molding and extrusion without degradation.

Specification

Chemical and Flame Resistance:  When added to resins, N-PMI increases chemical resistance against acids, bases and solvents.  It also has inherent flame-retardant character; incorporating N-PMI into a polymer matrix can improve the material’s fire resistance, a critical property for electronics and construction applications.

Photosensitivity and Biocidal Activity:  N-Phenylmaleimide is used in photosensitive resins and coating formulations due to its ability to undergo UV-initiated polymerization.  Uniquely, it possesses disinfectant properties – it is listed as a *bactericide, fungicide and underwater organism repellent*.  This makes it useful as an antifouling additive in marine coatings and as an intermediate in agricultural chemicals (e.g. plant-growth regulators and pesticides).

Solubility

N-Phenylmaleimide is highly soluble in many organic solvents (e.g. acetone, DMF, benzene), facilitating its use in reactive extrusion and solution polymerizations.  In summary, its combination of heat resistance, mechanical reinforcement, flame-retardancy and biocidal effects make N-phenylmaleimide a versatile monomer and modifier in advanced polymer systems.

Chemical Structure
Chemical Formula	C10H7NO2
Molecular Weight	173.16
CAS No.	941-69-5
Packing Type	Paper bag (20 kg)

Applications in Polymers and Alloys

• N-Phenylmaleimide manufactured by Yangchen Tech is primarily used as a comonomer modifier to produce heat-resistant plastic alloys and copolymers. 
• Heat-Resistant ABS (Acrylonitrile-Butadiene-Styrene):  N-PMI is widely added to ABS resin to create *N-PMI–modified ABS*, often called heat-resistant ABS.  The maleimide group copolymerizes with styrenic monomers, greatly improving HDT and thermal stability.  Even 1% N-PMI raises ABS HDT by \~2 °C.  N-PMI–ABS finds use in automotive parts (dashboards, engine covers), electronics housings and any application requiring high-temperature performance.
• PVC and PVC/ABS Blends:  Blending N-PMI into PVC or PVC/ABS alloys increases softening temperature and heat deflection.  For example, N-PMI improves the heat resistance of PVC-ABS compounds used in television and office equipment housings.
• PMMA (Acrylic Resins):  In polymethyl methacrylate (PMMA) and other acrylic resins, N-PMI copolymerization boosts thermal endurance.  N-PMI-modified PMMA is suitable for optical components (discs, lenses) and lighting parts that must withstand higher service temperatures.
• Engineering Plastic Alloys:  N-PMI is incorporated into blends of engineering plastics such as polyamide (PA), polycarbonate (PC), and PBT.  These polymer alloys – used in automotive and appliance components – gain improved thermal stability from N-PMI modification.

Please consult us for more information about N-Phenylmaleimide polymer applications.Welcome Inquiry!

Electrostatic chuck is a key component widely used in semiconductor manufacturing for clamping and positioning semiconductor chips. In the past, China's semiconductor industry relied mainly on imports for electrostatic chucks, which brought great inconvenience to domestic semiconductor manufacturing.

In view of international trade friction and technology protection pressure, China decided to increase the localization of electrostatic chucks. However, to achieve this goal is not easy, facing a series of technical and market difficulties.

Technical breakthroughs in the arduous

As a high-precision component, electrostatic chucks require extremely low coefficient of friction, stable mechanical properties and high-precision positioning capability. In order to realize localization, Chinese semiconductor enterprises actively carry out technical research.

After years of efforts, domestic enterprises have made some breakthroughs. They have improved the process, optimized the material ratios, and developed some innovative design methods. These technological advances have significantly improved the performance of domestic electrostatic chucks.

Structure of electrostatic chuck

Conventional electrostatic chuck, the difference is that the surface of the electrostatic chuck insulation layer material is different, dark aluminum nitride, white alumina, the structure of the electrostatic chuck is divided into the following parts:

- Insulation layer: Used for contact with wafers, usually aluminum nitride ceramic, because of its good mechanical strength, high temperature resistance and thermal conductivity.

- Ejector pin and He air holes: The ejector pin is used for wafer transfer. When the wafer enters the etching chamber, the ejector pin rises to take up the wafer, and then the ejector pin falls down to place the wafer on the surface of the electrostatic chuck. Moreover, the ejector is usually a hollow structure, and He gas is passed through to cool down the wafers at the same time. 

- Back He flow: Used to enhance heat dissipation and to provide feedback on wafer adsorption.

- Electrostatic Electrodes: Used to generate an electrostatic field to adsorb wafers. Electrodes are usually flat and embedded or deposited in insulating materials. Commonly used materials include aluminum, copper and tungsten and other metals with good electrical conductivity.

 - Circulating cooling water and heating electrodes: mainly used for the overall temperature control of the electrostatic chuck, heating electrodes and circulating cooling water at the same time, so that the wafer can be maintained at a stable temperature. 

The key and difficult point of the electrostatic chuck lies in the temperature control.

Semiconductor process temperature control of the wafer is critical to dry etching, for example, the need to control the wafer at 100 ° C to -70 ° C at a particular temperature to maintain a certain etching characteristics, and therefore the need for static chuck on the wafer to heat or heat dissipation, so as to accurately control the wafer temperature.

With the development of a new generation of semiconductor technology, low-temperature etching and deposition processes usually require wafers to reach lower temperatures, so the heat dissipation performance of the electrostatic chuck has put forward higher requirements.

From a technical point of view, in addition to the size of the wafers carried by the gradual increase in size, the development trend of electrostatic chuck is mainly manifested in the temperature uniformity control needs to improve, that is, the number of zoned temperature-controlled temperature zones gradually increased.

Before and after 2000, the number of zoned temperature control temperature zone is generally 2 zones, 2000 to 2005, the number of zoned temperature control temperature zone is generally 4 zones, and at this stage, there are more than 100 temperature zone of the electrostatic chuck products have been developed and put into practical applications.

The bright future of domestic electrostatic chuck

Although the road to localization faces difficulties and challenges, but the domestic semiconductor enterprises in the localization of electrostatic chuck has made remarkable progress. With the continuous maturation of technology and brand enhancement, the market share of domestic electrostatic chucks is gradually increasing. And, China as the world's largest semiconductor market, the demand for electrostatic chucks will continue to grow.

The localization of electrostatic chucks is an important part of China's semiconductor industry to achieve self-control. Although facing technical breakthroughs and market competition in the arduous, but China's semiconductor enterprises are actively promoting the localization of electrostatic chuck process. It is believed that with the passage of time, the domestic electrostatic chuck will be more mature and show strong competitiveness in the market.

About Xiamen Juci Technology Co., Ltd.

Xiamen Juci Technology Co., Ltd. is a cutting-edge high-tech enterprise dedicated to the R&D, manufacturing, and distribution of premium aluminum nitride (AlN) materials. As an industry-leading AlN powder producer, we deliver high-performance material solutions tailored for advanced applications in electronics, semiconductor, and aerospace sectors. Our commitment to excellence in product quality and customer service has established us as a trusted global partner for specialized ceramic materials.

Media Contact:
Xiamen Juci Technology Co., Ltd.

Phone: +86 592 7080230
Email: miki_huang@chinajuci.com

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Polyacrylamide (PAM) offers several advantages in the steel industry. Here are some of its key benefits:

1. Scale Inhibition: PAM can effectively inhibit the formation of scale in various stages of steel production, such as during descaling and cooling processes. Scale formation can lead to reduced heat transfer efficiency, equipment corrosion, and operational issues. PAM helps prevent the precipitation and deposition of scale-forming minerals, thus maintaining the efficiency of the production process.

2. Flocculation and Sedimentation: PAM can act as a flocculant, facilitating the aggregation of suspended particles in process water or wastewater generated during steel production. It improves the sedimentation and clarification processes, allowing for the efficient removal of solid particles and impurities. This results in cleaner process water and reduced environmental impact.

3. Water Treatment: PAM is widely used in wastewater treatment systems in the steel industry. It aids in the removal of organic and inorganic contaminants, heavy metals, oil, and grease from wastewater, ensuring compliance with environmental regulations. PAM can enhance the efficiency of processes such as coagulation, flocculation, sedimentation, and filtration.

4. Enhanced Filtration: In steel production, PAM can improve the filtration efficiency by forming larger and denser flocs, which are easier to separate from liquid. This helps in achieving higher filtration rates and better quality of filtrate, reducing the incidence of clogged filtration equipment and improving overall production efficiency.

5. Rheology Control: PAM can modify the rheological properties of fluids used in steel processing. By adjusting the viscosity and flow behavior of these fluids, PAM aids in controlling the spreading, coating, and casting processes. It enables precise control over the fluid's characteristics, facilitating uniform product quality.

6. Solid-Liquid Separation: PAM is effective in solid-liquid separation processes employed in the steel industry, such as centrifugation and filtration. It improves the dewatering efficiency of sludge generated during wastewater treatment, reducing the moisture content of the sludge and facilitating its disposal or further treatment.

Overall, the use of polyacrylamide in the steel industry provides benefits such as improved scale inhibition, enhanced flocculation and sedimentation, efficient water treatment, enhanced filtration, rheology control, and effective solid-liquid separation. These advantages contribute to increased productivity, cost savings, environmental compliance, and improved product quality in the steel manufacturing process.

Polyacrylamide (PAM) has some advantages in the field of sugar production, mainly including the following points:

1. Clarifying suspended liquids: Polyacrylamide is an excellent flocculant that can be used in the sugar industry to clarify syrups or suspended liquids and help separate solid particles or impurities suspended in the liquid.

2. Improving syrup filtration efficiency: PAM can improve the filtration performance of syrups, improve filtration efficiency, reduce energy consumption and increase production efficiency.

3. Improving sedimentation effect: The application of polyacrylamide can help sugar mills improve sedimentation effects, reduce suspended matter concentrations, and make impurities in sugar liquids precipitate more thoroughly.

4. Enhancing flocculation effect: Polyacrylamide as a flocculant can enhance the flocculation effect in sugar mills, reduce the dispersion of suspended matter in liquids, and promote the rapid sedimentation of solid particles.

5. Reducing energy consumption: By utilizing the flocculation and filtration properties of polyacrylamide, sugar mills can reduce energy consumption in water treatment processes and reduce production costs.

In general, polyacrylamide can play the role of clarification, separation, filtration, and improving production efficiency in the field of sugar production, and is an important auxiliary agent.

Ethylene-VinylAlcohol Copolymer (EVOH) resin provides a superior barrier against oxygen permeation, exhibiting performance up to four orders of magnitude greater than conventional polyethylene. Due to its excellent barrier properties, formability, and environmental friendliness, it is widely used in high-end new material fields such as automotive fuel tanks, films, food containers, and underfloor heating pipes.

When it comes to food packaging, EVOH really helps keep food fresh and flavorful for a long time, sometimes even years, without needing preservatives.

EVOH( EW-3201&EVAL F105B)is made bycombining ethylene and vinyl alcohol.

Applications

 1.Packaging

EVOH is often used with other materials for packaging since it's such a strong barrier:

Food & Beverage: It’s used for items like milk, juice, seafood, and other things that spoil quickly. For example, Chinese seafood exporters use five-layer vacuum-sealed films made of PE, EVOH, and PA.

Non-Food: You’ll find it in chemicals, cosmetics, pharmaceuticals, and electronics packaging.

2. Automotive

Fuel Tanks: EVOH mixed with HDPE makes lightweight and affordable plastic fuel tanks.

Structure :

Outer layer (HDPE) → Recycled layer → Adhesive layer (LLDPE) → Barrier layer (EVOH) → Adhesive layer (LLDPE) → Inner layer (HDPE).

Fuel Lines: PA-EVOH composite tubes replace metal pipes, aiding vehicle lightweighting.

3. Medical

Selective Permeable Membranes: Sterilized via radiation (e.g., EVOH hollow fibers for dialysis).

Artificial Kidneys: Hollow-fiber membranes for blood purification.

Drug Delivery: EVOH-coated polymers for controlled-release medications.

Biomedical Implants: Blends with corn starch or cellulose acetate for bone substitutes and tissue repair.

4. Construction

Heating Pipes: EVOH’s oxygen barrier prevents corrosion in heating systems.

Types: 3-layer (external barrier) and 5-layer (internal barrier) pipes, both using EVOH.

5. Other Uses

Textiles: Heat-sealing adhesives with superior wash resistance for apparel.

Hydrogen Storage: EVOH-modified hydrogen tank liners maintain elasticity and barrier performance even at low temperatures.

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Ultrafiltration membranes are super popular for separating different substances. You can find them in areas like oil processing, textiles, biopharmaceuticals, food production, wastewater treatment, and even making drinking water. Scientists are exploring ways to enhance these membranes so they can produce more water without compromising their filtering ability and also reduce pollution. To this end, many scholars are committed to developing new membrane materials and modifying membranes to improve their application effects. There are many methods to modify membrane materials, such as copolymerization, mixing and surface modification. Blending is simple and easy, making it a popular topic in membrane research. That's why many scientists in the field pay attention to it.

Polyvinyl alcohol (PVA 088-08 & PVA 1088)  has good film-forming properties and pollution resistance, and is widely used as a material for preparing hydrophilic membranes.PVA membranes have a tendency to swell and can even dissolve, so they often need some changes, like heat treatment or blending. 

To make these membranes, we used materials like polyvinyl alcohol (PVA), cellulose acetate (CA), glacial acetic acid, metal chlorides, and water. We created blended ultrafiltration membranes using a method called phase inversion, adding metal chlorides like sodium chloride (NaCl), potassium chloride (KCl), and barium chloride (BaCl). We checked how the amount of these metal chlorides impacted the performance of the blended membranes.

Our results showed that when the mass fraction of NaCl and KCl doesn't go over 1% in the membrane solution, the modified blended membrane performs well in retaining substances. The pure water flow increases, while energy use stays pretty much the same. But, when the mass fraction goes above 1.5%, the water flow jumps significantly, but the retention rate drops. We found that about 1% is the best amount for the alkali metal chlorides, while for BaCl, around 1.5% works best. Under the same conditions, blending with KCl results in the highest water flow rate. After we changed the PVA-CA blended membrane with NaCl and KCl, it became more water-loving. But when we used BaCl, it got a bit less water-loving.

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In this era of rapid technological advancement, the development and application of new materials have become a crucial driving force for progress. Polyvinyl butyral resin (PVB), as an exceptional polymer material, demonstrates tremendous potential across various fields. This article provides an in-depth exploration of PVB's chemical properties, production processes, and its extensive applications in modern technology, offering readers a comprehensive understanding of the scientific principles and technological appeal behind this remarkable material.

• Fundamental Characteristics of Polyvinyl Butyral

Polyvinyl butyral is a type of plastic made by combining polyvinyl alcohol and butyraldehyde. It boasts outstanding features including high transparency, excellent flexibility, and strong weather resistance. 

• PVB Production Process Flow

1. Raw material preparation: Polyvinyl alcohol and n-butyraldehyde as primary materials;

2. Condensation reaction: Polyvinyl alcohol is dissolved in hot water with catalyst, followed by gradual addition of butyraldehyde solution to form PVB prepolymer;

3. Dehydration and drying: The obtained PVB prepolymer undergoes dehydration and drying processes;

4. Pelletizing and forming: Finally, the dried PVB powder is processed into desired shapes or specifications through extrusion and pelletizing techniques.

Application Fields of Polyvinyl Butyral

1. Automotive industry:  PVB safety glass is great at preventing injuries from shattered glass and is often found in windshields;

2. Construction sector: PVB laminated glass makes windows safer, helps with insulation, and blocks noise, making homes cozier;

3. Electronics industry:Its strong adhesion and durability make PVB resin a good choice for different packaging and printing inks;

4. Packaging and printing: With excellent adhesion and wear resistance, PVB resin is suitable for various packaging coatings and printing inks.

Future Development Trends

Ongoing research focuses on optimizing PVB(PVB SD-1&PVB B-20HX)synthesis processes and expanding its applications.  Environmental considerations have also made the development of biodegradable PVB a current research priority.

With its outstanding comprehensive performance, polyvinyl butyral is playing an increasingly vital role across multiple industries. As technology advances, we can confidently anticipate that PVB will continue to deliver more surprises and transformations. 

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• Polyvinyl Alcohol 452 Properties Properties

Polyvinyl alcohol (PVOH, PVOH452&Alcotex 45) is a water-soluble synthetic polymer. PVOH has excellent film-forming and adhesive properties, making it an ideal material for the production of films and adhesives. PVOH also has strong resistance to oil, grease and organic solvents. It is commonly used in packaging, textiles and coatings for a variety of purposes.

• Applications of Polyvinyl Alcohol 452

PVOH is a versatile polymer that can be widely used in different industries.In the food industry, it's popular as a packaging material because it does a great job at keeping moisture and oxygen out. PVOH is a very popular material. The film formed by PVOH can also be used as an adhesive layer for different types of films, making it an important component of flexible packaging. In addition, PVOH can also be used in the production of laundry detergent pods. It is a water-soluble packaging material that dissolves in water during the washing process.

In the medical field, PVOH is used to create water-soluble films for blister packs. These films help keep medicines safe from moisture and spoilage. It can also be used in medical textiles and surgical dressings. PVOH works as a binder for making gypsum-based products. It's really handy in construction because it makes the final products stick better and last longer. In farming, PVOH is used for coating seeds and in fertilizers that gradually release nutrients.

• Recyclability of Polyvinyl Alcohol 452

Polyvinyl alcohol (PVOH, PVOH452&Alcotex 45) is a recyclable material, and the recycling process involves dissolving it in water to break down its molecular structure, making it easier to separate from any impurities. The resulting solution is filtered and the PVOH is then regenerated by removing the water from the solution. The regenerated PVOH can be used to produce a variety of products such as compostable bags, water-soluble films, and adhesives.

Recycling PVOH is essential to reduce the amount of plastic waste in the environment and conserve resources. In addition, PVOH is biodegradable, which means that it can be broken down by microorganisms and eventually decomposed into natural compounds. Therefore, recycling PVOH not only reduces waste, but also reduces the amount of plastic waste in landfills and oceans, which has a positive impact on the environment.

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