LIWEI CHEMICAL CO. LTD
Grades |
Hydrolysis |
Volatiles |
Viscosity |
Ash |
PH Value |
Purity |
Grades are being produced regularly |
||||||
PVA1788 |
87.0-89.0 |
5 |
20.5-24.5 |
0.4 |
5-7 |
93.5 |
PVA1888 |
86.0-90.0 |
6 |
23.5-28.5 |
0.5 |
5-7 |
92.5 |
PVA1895 |
94.0-96.0 |
5 |
26.0-30.0 |
0.5 |
5-7 |
93.5 |
PVA1799 |
98.0 99.4 |
5 |
23.0-29.0 |
0.7 |
5-7 |
93.0 |
PVA2488 |
87.0-89.0 |
5 |
45.0-55.0 |
0.5 |
5-7 |
93.5 |
|
||||||
PVA0499 |
98.0 99.4 |
5 |
4.0-5.0 |
0.7 |
5-7 |
93.0 |
PVA0498 |
98.0 98.8 |
5 |
4.0-5.0 |
0.7 |
5-7 |
93.0 |
PVA0588 |
87.0-89.0 |
5 |
4.5-6.0 |
0.7 |
5-7 |
93.0 |
PVA0599 |
98.0-99.0 |
5 |
5.0-6.5 |
0.7 |
5-7 |
93.0 |
PVA1098 |
97.0-99.0 |
5 |
8.0-12.0 |
0.5 |
5-7 |
93.5 |
PVA1399 |
98.0-99.0 |
5 |
13.0-17.0 |
0.5 |
5-7 |
93.5 |
PVA1388 |
87.0-89.0 |
5 |
12.0-14.0 |
0.5 |
5-7 |
93.5 |
PVA1797 |
96.0-98.0 |
7 |
23.0-29.0 |
0.7 |
5-7 |
93.5 |
PVA2088 |
87.0-89.0 |
5 |
29.0-34.0 |
0.5 |
5-7 |
93.5 |
PVA2497 |
96.0-98.0 |
5 |
54.0-64.0 |
0.5 |
5-7 |
93.5 |
PVA2499 |
98.0-99.0 |
5 |
55.0-65.0 |
0.5 |
5-7 |
93.5 |
Grades can be produced |
||||||
PVA1897 |
96.0-98.0 |
5 |
27.0-31.0 |
0.5 |
5-7 |
93.5 |
PVA1795 |
94.0-96.0 |
7 |
22.0-28.0 |
0.5 |
5-7 |
93.5 |
PVA1899 |
98.0-99.0 |
5 |
28.0-32.0 |
0.5 |
5-7 |
93.5 |
PVA2099 |
98.0-99.0 |
5 |
34.0-39.0 |
0.5 |
5-7 |
93.5 |
PVA2288 |
87.0-89.0 |
5 |
38.0-42.0 |
0.5 |
5-7 |
93.5 |
PVA1792 |
91.0-93.0 |
5 |
21.0-27.0 |
0.5 |
5-7 |
93.5 |
PVA2092 |
91.0-93.0 |
5 |
28.0-34.0 |
0.5 |
5-7 |
93.5 |
Name | ||
---|---|---|
Polyvinyl Alcohol 1788 & Polyvinyl Alcohol 1799 PVA 1788 & PVA 1799 | Order | Detail |
Polyvinyl Alcohol 0588 & Polyvinyl Alcohol 0599 PVA 0588 & PVA 0599 | Order | Detail |
Polyvinyl Alcohol 2488 & Polyvinyl Alcohol 2499 PVA 2488 & PVA 2499 | Order | Detail |
Polyvinyl Alcohol 0488 & Polyvinyl Alcohol 0499 PVA 0488 & PVA 0499 | Order | Detail |
Polyvinyl Alcohol 1492 & Polyvinyl Alcohol 1498 PVA 1492 & PVA 1498 | Order | Detail |
Polyvinyl Alcohol 1792 & Polyvinyl Alcohol 1798 PVA 1792 & PVA 1798 | Order | Detail |
Polyvinyl Alcohol 2088 & Polyvinyl Alcohol 2099 PVA 2088 & PVA 2099 | Order | Detail |
Polyvinyl Alcohol 2699 PVA 2699 | Order | Detail |
Packing | Our polyvinyl alcohol products are packed in craft paper bag. Net weight 12.5kgs or 20kgs if floccule, Net weight 25kgs /20kgs if powder or Granule. |
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Storage | Powder 20°C 2 years; Floccule 20°C 2 years. |
Shipping | Room temperature 5-30℃ in China; may vary elsewhere |
Liwei PVA is one of the top 10 PVA factories and the top 100 strongest enterprises in anhui province.In 2010,Liwei PVA is evaluated as advanced and high technical company. We mainly deals in polyvinyl alcohol,PVA,PVA fiber and raw materials for producing PVA like vinyl acetate,calcium carbide. |
For samples, pricing, or more information, please call us at 0086-25-52397803 or mail to info@china-pva.net or fill out the following form. We will respond to you as soon as possible. |
Tel: 0086-25-52397803
E-mail: info@china-pva.net
Common Names | Polyvinyl Alcohol | ||
---|---|---|---|
Structure | (C2H4O)n | ||
CAS No. | 9002-89-5 | Boiling Point(℃) | 23.5±13.0 |
Molecular Weight | 44.0526 | Melting Point(℃) | 200 °C |
Appearance | White crystalline | Vapor Specific Gravity | No data available |
HS Code | 390530 | Flash Point(℃) | No data available |
Solubility | Soluble in water (above 95℃), slightly soluble in dimethyl sulfoxide | Autoignition Temperature(℃) | No data available |
Safety Phrases | None | ||
---|---|---|---|
RIDADR | None | ||
WGK Germany | None | ||
Packaging Group | None | ||
Hazard Class | None | ||
SYMPTOMS | PREVENTION | FIRST AID | |
Inhalation | None | None | If breathed in, move person into fresh air. If not breathing, give artificial
respiration. Skin |
Skin | None | None | Wash off with soap and plenty of water. Eyes |
Eyes | Redness | None | Flush eyes with water as a precaution. |
Ingestion | Nausea. Vomiting | None | Never give anything by mouth to an unconscious person. Rinse mouth with water. |
PVA is produced with calcium carbide as raw material. After calcium carbide reacts with water to form acetylene, acetylene synthesizes with acetic acid to form vinyl acetate, then methanol is used as the solvent to polymerize, Through alcoholysis, poly-vinyl acetate changes to PVA. After being crushed and dried, it becomes finished product. |
Polyvinyl alcohol, abbreviated as
PVOH, PVA, or PVAl, is a synthetic
polymer that is colorless, odorless, and water-soluble. It usually appears in the formation
of white, flaky, fluffy, or powdery solids. Polyvinyl alcohol (PVA) has a history dating
back to the early 20th century. It was first discovered and synthesized in 1924 by German
chemists W.O. Hemnann and W. Hachnel. At that time, PVA's main application areas were
adhesives and processing aids for cellulose fibers.
In the 1950s, PVA began to be produced on a large scale industrially and gradually expanded
into many fields, such as textile, paper, printing, and construction. Subsequently, with the
progress of science and technology, its application areas continue to expand, and it is now
widely used in food, medicine, cosmetics, electronics, environmental protection, and many
other fields.
Specifically, in China, the research and development of PVA began in 1951, and in the 1970s,
PVA commodities began to appear on the market. As a result of the continuous improvement of
synthetic technology and decreasing prices, the use of PVA is becoming increasingly
widespread, and the development is proceeding at a rapid pace.
Properties: Polyvinyl alcohol (PVA) is a versatile water-soluble polymer with properties
between those of plastics and rubber.
Polyvinyl Alcohol is a solid that can be in the form of a white powder, flakes, or flocs,
with a glass transition temperature of 60-85°C. Polyvinyl alcohol is soluble in polar water
due to its many polar alcohol groups that can form hydrogen bonds with water. It is also
soluble in hot hydroxyl-containing solvents such as glycerol and phenol but insoluble in
general organic solvents like methanol, benzene, acetone, and gasoline.
Classification: The polymerization degree determines the molecular weight, which can be
classified into four categories: ultra-high degree of polymerization (250,000-300,000), high
degree of polymerization (170,000-220,000), medium degree of polymerization
(120,000-150,000), and low degree of polymerization (25,000-35,000). Alcoholysis degree
generally has complete alcoholysis (alcoholysis degree 98-100%), partial alcoholysis
(alcoholysis degree 87-89%) and alcoholysis degree 78%. Generally, the thousand or hundred
digits of the degree of polymerization are put in the front, and the degree of alcoholysis
is put in the back of the product grade; for example, polyvinyl
alcohol 17-99 means that the degree of polymerization is 1.7k, and the degree of
alcoholysis is 99%.
Polyvinyl alcohol (PVA) has a wide range of applications due to its unique properties as a
water-soluble polymer. Here are some of the main uses of PVA:
Textile Industry: PVA is commonly used as a sizing agent in the textile industry. It acts as
a binder between yarn and other fibers, improving their strength and abrasion resistance. It
also helps in the smooth operation of weaving machines.
Adhesives and Binders: PVA is an excellent binder and adhesive component in various
applications. It can be used to manufacture glues, adhesives, and coatings for paper, wood,
and other materials. Its good adhesion properties make it suitable for laminating and
bonding tasks.
Paper and Coatings: PVA is used as a surface coating agent in the paper industry. It
improves the surface properties of paper, such as gloss, printability, and water resistance.
PVA coatings can also be applied to other materials to enhance their durability and
appearance.
Film and Membrane Formation: PVA can be processed into thin films or membranes with specific
properties. These films are used in various applications, including packaging, separation
membranes for water treatment or dialysis, and as substrates for electronic
components.
Fiber Production: PVA fibers, known as vinyl, are produced from PVA solutions. These fibers
have excellent tensile strength and resistance to chemicals, making them suitable for use in
clothing, ropes, and other industrial applications.
Emulsion and Suspension Polymerization: PVA solutions can serve as protective colloids in
emulsion and suspension polymerization reactions, stabilizing the dispersed particles and
promoting the formation of uniform polymer particles.
Paints and Coatings: PVA is used as a binder in water-based paints and coatings. It helps to
improve the adhesion, durability, and appearance of the coatings on various surfaces.
Biomedical Applications: PVA and its derivatives have also found applications in the
biomedical field. They can be used to produce biodegradable implants, drug delivery systems,
and tissue engineering scaffolds.
It's worth noting that the specific applications of PVA can vary depending on its molecular
weight, degree of polymerization, and alcoholysis level. Manufacturers often tailor the
properties of PVA to meet the requirements of specific end-use applications.
The production of polyvinyl alcohol (PVA) involves a number of steps, mainly including raw
material preparation, polymerization reaction, purification, and processing. The following
is the basic process of polyvinyl alcohol production:
Raw material preparation: The main raw material for polyvinyl alcohol is ethylene. Ethylene
is usually an organic compound extracted from petroleum or natural gas, either by fractional
distillation of alkanes in the petroleum refining process or by cracking hydrocarbons in
petroleum.
Polymerization of ethylene: Ethylene is converted to polyethylene through a polymerization
reaction. This step is usually performed by catalyst-initiated free radical polymerization.
In the polymerization reaction, the double bonds in the ethylene molecule are opened and
connected to form long chains.
Polyethylene conversion: Polyethylene is further converted to polyvinyl alcohol. This
conversion process can be acid-catalyzed, base-catalyzed, or enzyme-catalyzed. In this step,
some of the hydrogen atoms in the polyethylene chain are replaced by hydroxyl groups (OH) to
produce polyvinyl alcohol.
Purification and processing: The synthesized polyvinyl alcohol is purified and processed to
remove impurities and meet specific product requirements, including steps such as solvent
extraction, crystallization, and drying.Polyvinyl alcohol is usually used in granular form.
The dried polyvinyl alcohol is fed into a pelletizing machine, where it is made into pellets
by extrusion and cutting.
In addition to the basic steps described above, the polyvinyl alcohol production process can
be fine-tuned for different raw materials and catalyst choices. Domestic production
processes for polyvinyl alcohol mainly include calcium carbide acetylene, petroleum
ethylene, natural gas acetylene, and bio-ethylene, with calcium carbide acetylene accounting
for the largest share of production processes.
Packages:20 kg/bag,25 kg/bag,500 kg/bag,1000kg/bag.
Storage:Polyvinyl alcohol should be
packaged in sealed woven bags or cartons lined with plastic bags to prevent the ingress of
moisture and other impurities.
Transportation:Vehicles transporting polyvinyl alcohol
should be protected from moisture, sun and rain to keep the interior dry and clean to
prevent possible chemical reactions or quality changes of the polyvinyl alcohol in a humid
environment.
Polyvinyl alcohol is generally a non-toxic material, but its dust can be irritating to the respiratory tract. Polyvinyl alcohol was included in the list of group 3 carcinogens in the preliminary collation of the list of carcinogens published by the World Health Organisation's International Agency for Research on Cancer in 2017. Therefore, prolonged exposure to high concentrations of polyvinyl alcohol may pose a potential health risk. Staff should be well protected in case of contact and should immediately flush with running water if it touches their eyes and skin. Operations should be carried out in a well-ventilated environment.