Moreover, the global nature of wholesale manufacturing demands an understanding of international regulations and standards
Pure PVB is non-toxic and harmless to human body. In addition, ethyl acetate or alcohol can be used as solvent, so PVB is widely used in printing ink of food containers and plastic packaging in European and American countries.
Storage safety properties
PVB can be stored for two years without affecting its quality as long as it is not in direct contact with water; PVB shall be stored in a dry and cool place and avoid direct sunlight. Heavy pressure shall be avoided during PVB storage.
Solubility
PVB is soluble in alcohol, ketone, ester and other solvents. The solubility of various solvents changes according to the functional group composition of PVB itself. Generally speaking, alcohol solvents are soluble, but methanol is more insoluble for those with high acetal groups; The higher the acetal group, the easier it is to dissolve in ketone solvents and ester solvents;
PVB is easily soluble in cellosolve solvents; PVB is only partially dissolved in aromatic solvents such as xylene and toluene; PVB is insoluble in hydrocarbon solvents.
Viscosity characteristics of PVB solution
The viscosity of PVB solution is greatly affected by the formula of solvent and the type of solvent; Generally speaking, if alcohol is used as solvent, the higher the molecular weight of alcohol, the higher the viscosity of PVB solution;
Aromatic solvents such as xylene and toluene and hydrocarbon solvents can be used as diluents to reduce the viscosity of PVB solution; The effect of PVB chemical composition on viscosity is summarized as follows: under the same solvent and the same content of each base, the higher the degree of polymerization, the higher the solution viscosity; Under the same solvent and the same degree of polymerization, the higher the acetal group or acetate group, the lower the solution viscosity.
Dissolution method of PVB
Where mixed solvents are used, the dissolution step is to first put aromatic solvents (such as xylene, toluene, etc.) or ester solvents (such as n-butyl acetate, ethyl acetate, etc.) into the mixing, slowly put PVB into the mixing, and then add alcohol solvents (such as n-butanol, ethanol, etc.) after PVB is dispersed and expanded,
At this time, the dissolution time can be shortened by heating; Using this dissolution method, the formation of lumpy PVB can be avoided (because the dissolution time will be several times after the formation of lumpy PVB), so the dissolution speed can be accelerated. Generally, the ratio of aromatic and alcohol solvents is 60 / 40 ~ 40 / 60 (weight ratio), and PVB solution with low viscosity can be prepared.
The solvent composition contains 2 ~ 3wt% water, which can improve the hydrogen bonding strength of alcohol solvents and help the solubility of PVB.
Processing properties
Although PVB resin is a thermoplastic, it has little processability before plasticizer is added. Once plasticizer is added, its processability is very easy.
The purpose of general coatings and adhesives is to change the resin characteristics by adding plasticizers to meet the application requirements, such as film softness, reducing the TG point of the resin, reducing the heat sealing temperature, maintaining low-temperature softness, etc.
Compatibility
PVB can be compatible with a variety of resins, such as phenolic resin, epoxy resin, alkyd resin and MELAMINE resin.
B-08sy, b-06sy and b-05sy with high acetal degree can be mixed with nitrocellulose in any proportion. PVB and alkyd resin are partially compatible. General PVB is compatible with low molecular weight epoxy resin, while high molecular weight epoxy resin needs PVB with high acetal degree to be compatible with each other.
Pure PVB is non-toxic and harmless to human body. In addition, ethyl acetate or alcohol can be used as solvent, so PVB is widely used in printing ink of food containers and plastic packaging in European and American countries.
Storage safety properties
PVB can be stored for two years without affecting its quality as long as it is not in direct contact with water; PVB shall be stored in a dry and cool place and avoid direct sunlight. Heavy pressure shall be avoided during PVB storage.
Solubility
PVB is soluble in alcohol, ketone, ester and other solvents. The solubility of various solvents changes according to the functional group composition of PVB itself. Generally speaking, alcohol solvents are soluble, but methanol is more insoluble for those with high acetal groups; The higher the acetal group, the easier it is to dissolve in ketone solvents and ester solvents;
PVB is easily soluble in cellosolve solvents; PVB is only partially dissolved in aromatic solvents such as xylene and toluene; PVB is insoluble in hydrocarbon solvents.
Viscosity characteristics of PVB solution
The viscosity of PVB solution is greatly affected by the formula of solvent and the type of solvent; Generally speaking, if alcohol is used as solvent, the higher the molecular weight of alcohol, the higher the viscosity of PVB solution;
Aromatic solvents such as xylene and toluene and hydrocarbon solvents can be used as diluents to reduce the viscosity of PVB solution; The effect of PVB chemical composition on viscosity is summarized as follows: under the same solvent and the same content of each base, the higher the degree of polymerization, the higher the solution viscosity; Under the same solvent and the same degree of polymerization, the higher the acetal group or acetate group, the lower the solution viscosity.
Dissolution method of PVB
Where mixed solvents are used, the dissolution step is to first put aromatic solvents (such as xylene, toluene, etc.) or ester solvents (such as n-butyl acetate, ethyl acetate, etc.) into the mixing, slowly put PVB into the mixing, and then add alcohol solvents (such as n-butanol, ethanol, etc.) after PVB is dispersed and expanded,
At this time, the dissolution time can be shortened by heating; Using this dissolution method, the formation of lumpy PVB can be avoided (because the dissolution time will be several times after the formation of lumpy PVB), so the dissolution speed can be accelerated. Generally, the ratio of aromatic and alcohol solvents is 60 / 40 ~ 40 / 60 (weight ratio), and PVB solution with low viscosity can be prepared.
The solvent composition contains 2 ~ 3wt% water, which can improve the hydrogen bonding strength of alcohol solvents and help the solubility of PVB.
Processing properties
Although PVB resin is a thermoplastic, it has little processability before plasticizer is added. Once plasticizer is added, its processability is very easy.
The purpose of general coatings and adhesives is to change the resin characteristics by adding plasticizers to meet the application requirements, such as film softness, reducing the TG point of the resin, reducing the heat sealing temperature, maintaining low-temperature softness, etc.
Compatibility
PVB can be compatible with a variety of resins, such as phenolic resin, epoxy resin, alkyd resin and MELAMINE resin.
B-08sy, b-06sy and b-05sy with high acetal degree can be mixed with nitrocellulose in any proportion. PVB and alkyd resin are partially compatible. General PVB is compatible with low molecular weight epoxy resin, while high molecular weight epoxy resin needs PVB with high acetal degree to be compatible with each other.
Titanium dioxide manufacturer: Panzhihua Dongfang
A study published in the Journal of Agricultural and Food Chemistry in 2019 sought to examine the effects of titanium dioxide on intestinal inflammation. Researchers did this by feeding rats titanium dioxide nanoparticles and found that, after the course of two to three months, the animals had lower body weights and induced intestinal inflammation. The researchers also found the nanoparticles altered gut microbiota composition and aggravated chronic colitis. The rats also experienced reduced populations of CD4+T cells (which are cells that help organize immune responses by prompting other immune cells to fight infection), regulatory T cells, and white blood cells in mesenteric lymph nodes. The researchers wrote: “Dietary TiO2 nanoparticles could interfere with the balance of the immune system and dynamic of gut microbiome, which may result in low-grade intestinal inflammation and aggravated immunological response to external stimulus, thus introducing potential health risk.”
CaS0 4 + 20H— → SO/— + Ca (0H) 2
Cold galvanized wire refers to a process in which ordinary steel wire is treated by cold galvanized and a zinc layer is attached to its surface. Cold galvanized wire has the advantages of anti-corrosion and anti-wear, and is widely used in construction, machinery, automobile, electronics and other industries. The following will introduce the production process and flow of cold galvanized wire.
Flexibility because the wire is different from other stainless steel raw materials, it is low density so in the flexibility of the appropriate excellent, it can be described according to people’s fantasy into all kinds of different shapes. Some large enterprises will buy hook flower net products, its reasons are no more than two, one is to prevent people outside the enterprise to walk around at will, the second is to advance the whole image of the enterprise. Therefore, under the premise that the protection requirements are not high, galvanized hook net can play a role in its use, the appearance of flexible hook net is settled to the use of address, from a distance and look at it like a work of art quite appreciate the meaning.
- Performance characteristics of zinc coating: zinc layer of thick galvanized wire zinc layer crystallinity meticulous, uniform and no gap, good corrosion resistance; The zinc layer obtained by electrogalvanizing is very pure and corrodes slowly in the gas, liquid and fog of acid and alkali, which can effectively protect the steel matrix. Galvanized layer can also be chromic acid passivation treatment into a variety of colors, beautiful and generous, with good decorative; The zinc layer on the galvanized wire has good ductility, can be cold blanking, rolling, bending and other molding without damage to the zinc layer.
- It is recommended to have a brush, comb or rake ready before bathing your dog; Shampoo, conditioner, shower gloves, tether, bath mat, floor drain lid, spray, towel and shower shower.
- The key and important parts with tensile strength greater than 1034Mpa should be relieved of stress at 200±10℃ for more than 1 hour before plating, and the carburized or surface hardened parts should be relieved of stress at 140±10℃ for more than 5 hours. The cleaning agent used for cleaning shall have no effect on the binding force of the coating and no corrosion on the substrate. Acid activation Acid activation solution should be able to remove corrosion products and oxide film (skin) on the surface of parts without excessive corrosion on the matrix.
The barbed wire factory will store the inventory of the barbed wire blade in the appropriate place because of the understanding of the product characteristics.
- The color of powder coating is divided into: blade blue, grass green, dark green, yellow. Spray blade gill net by hot-dip galvanized steel plate or stainless steel sheet stamping out sharp knife sheet, high tension galvanized steel wire or stainless steel wire as the core of the resistance device. Because the barbed wire shape is not easy to contact, so it can reach an excellent barrier effect. The primary raw material of the product is galvanized sheet, stainless steel plate, high quality low carbon steel wire (electric galvanized, hot galvanized, plastic coated, plastic sprayed) wire, blue, green, yellow and other colors.
- 1, prepare for the bird cage
Galvanized hook mesh standard is thorough, mesh planning: 3cm-20cm, silk planning: 1.2mm-4.5mm, galvanized hook mesh 6000 square meters, some standards are available. Benefits: The selection of low carbon steel wire, surface for cold galvanized (electric galvanized) hot dip galvanized anticorrosion treatment, mesh wire strong, strong protection, long anticorrosion time.
- Hot dip galvanizing, also known as hot dip galvanizing, is a method of obtaining a metal covering by immersing a steel member in a molten zinc solution. With the rapid development of high-voltage transmission, transportation and communication, the protection requirements for steel parts are becoming higher and higher, and the demand for hot-dip galvanizing is also increasing. Usually the thickness of electric galvanized layer is 5 ~ 15μm, and the large roll galvanized wire layer is generally more than 35μm, even up to 200μm. Hot dip galvanizing has good covering ability, dense coating and no organic inclusions.
- Hongyu twist flower hexagonal mesh factory is the selection of low carbon steel silk woven, mesh structure he has the characteristics of corrosion resistance, high strength and ductility. Steel wire diameter up to 2.0mm-4.0mm, steel wire appearance is usually selected hot dip galvanized maintenance, galvanized maintenance layer thickness can be made according to customer needs, galvanized maximum can reach 300g/㎡.
The best way to manage off-road safety is to carry out management and protection from the source, maximize the safety of people’s lives and property, and reduce the non-operational costs of railway enterprises, which is a key content of railway safety work in the new era. At this time, it is necessary to install protective nets on both sides of the railway, which is what we usually say, blade barbed rope protective nets, which can prevent accidents.
The protective duration of galvanized iron wire is closely related to the thickness of galvanized iron wire. In general, zinc layer thickness needs to be very high in dry main gas and indoor applications, but in harsh environments. Therefore, in the selection of galvanized layer thickness, the impact of the environment should be considered. If galvanized iron wire products of different diameters are required, material selection and coating should be controlled reasonably.
Common galvanized iron wire equipment is usually used in barbecue net, barbecue net generally requires to have a long service life, with galvanized iron wire equipment to wire a layer of zinc, barbecue net is not easy to be corroded.
- Galvanized wire hook mesh is widely used in warehouses, east and west refrigeration, protective reinforcement, parks, zoo fences, Marine fishing fences and construction site fences, mechanical equipment protection. There are two kinds of use, that is, slope protection hook net (slope protection net), coal mine hook net (mine hook net, coal mine support net, roadway support net).
We compare the difference between galvanized welding net and other welding net by introducing in detail, and write the following to introduce its material: Galvanized welded wire mesh is made of low carbon wire, through automation of fine precision machinery equipment spot welding processing after forming, selection of disposal of the appearance of zinc leaching technology, produce practice British standard, with smooth surface neat, uniform layout to consolidate, the function is good, even if some sections or accept pressure also won’t attack lax appearances, it is the strongest anti-corrosion function in iron mesh, Screen mesh is iron use one of the most widely network class, excellent anticorrosive makes its popularity in the breeding, sucking the neat surface, increased the look and feel, can play will be decorating effect, this feature makes it reflected in the mining industry, because the select material of low carbon high quality material, make it unique iron mesh not usually have flexibility, Concluded that it is used in the process of plasticity, and then can be used for the deep processing of hardware technology, disorderly wall swing, underground leak-proof crack, light net body, make this cost is much lower than the cost of iron screen, more can understand its economy, benefits. Galvanized welding net can be used as poultry cage, egg basket, channel fence, drainage tank, porch fence, rat net, mechanical protective cover, livestock and plant fence, grid frame, etc. It is also widely used in industry, agriculture, construction, transportation, mining and other occupations.
- Uses of galvanized hexagonal net: building wall fixed, heat preservation, heat insulation; Power plant tie pipe, boiler warm; Anti-freezing, residential protection, landscaping protection; Raising chickens and ducks, isolating chicken and duck houses, plays a role in protecting poultry; To protect and support seawalls, hillsides, roads and Bridges and other waterworks.
Annealing wire is widely used because it has a good elasticity and flexibility, in the annealing process can be good control of its hardness, it is mainly made of iron wire, more often used in the construction industry binding wire use. In the production of the wire factory, annealing wire will be processed according to the properties of the material, according to the needs of different to change its hardness degree, can make it has more advantages, can reduce the consumption of metal, reduce the cost of production.
Bridge protection system generally do not need to be specially installed special drainage system, the use of hexagonal mesh made of gabion mesh box, the inside of the filler are selected stones, these stones are not easy to wear, and between the stones and stones will retain some gaps, so it is very good to meet the drainage requirements.