Question 1: What is the use of polyvinyl amide? There is no such thing as polyvinyl amide. You can find out by drawing the structural formula yourself.
Polyvinyl amide, from the naming point of view, the monomer should be vinyl amide. The amide structure is -CONH2, the oxygen atom is double-bonded to the carbon, the amino NH2 is connected to the carbon with a single bond, and the carbon has four valence bonds. In this way, three are used and only one is left. There is no way to form an alkene. double bond structure.
Acrylamide is CH2=CH-CONH2, and polyacrylamide is polymerized by opening double bonds.
Question 2: What is polyvinylamide? What is it used for? Polyvinylamide was not found, only acrylamide was found.
Acrylamide, also known as AM. The pure product is white crystal, easily soluble in water, methanol, ethanol, acetone, slightly soluble in ethyl acetate, chloroform, and slightly soluble in benzene. The acrylamide molecule has two active centers, capable of both weakly acidic and weakly alkaline reactions.
Uses
Acrylamide is mainly used to manufacture water-soluble polymers for oil mining, coal washing, papermaking, textiles, sewage treatment, metallurgy, sugar refining, construction, and medicine. and agriculture and other sectors.
Technical indicators
Acrylamide is available in liquid and solid forms.
Storage, transportation and precautions
Acrylamide is moderately toxic. The maximum daily exposure allowed for ordinary people does not exceed 0.0005mg/kg, and the oral dose for rats is LD500.7g/kg. Skin contact can cause poisoning, with symptoms such as erythema, peeling, dizziness, motor dysfunction, and limb weakness.
During storage and transportation, attention should be paid to ensuring the safety of humans and animals. It is strictly prohibited to inhale the product into the human body or touch the skin.
Acrylamide is a substance that is unstable to heat and moisture. Humidity and heat should be avoided during storage and transportation. Water-soluble ones are more susceptible to deterioration. The storage period of 98% solid acrylamide at room temperature shall not exceed 6 months. The storage period of liquid acrylamide ranges from 3 days to 3 months depending on the polymerization inhibitor and conductivity. It can still be used after the storage period if no self-aggregation occurs.
Question 3: How to distinguish polyethylene materials from nylon materials? The natural color of nylon is ivory and the natural color of POM is white. Polyacetal plastic is another excellent resin variety developed after nylon and has excellent comprehensive properties. Polyformaldehyde has good resistance to solvents, oils, weak acids, weak alkali and other properties. Polyoxymethylene has high hardness and rigidity, high creep resistance and stress relaxation capabilities, excellent wear resistance, and self-lubricating properties. The scientific name of polyoxymethylene is polyoxymethylene (POM), which is fatigue-resistant. A linear polymer with no side chains, high density and high crystallinity, with excellent comprehensive properties. The tensile strength of polyformaldehyde can reach 70MPa, it can be used for a long time at 104°C, its embrittlement temperature is -40°C, and it has low water absorption. However, polyformaldehyde has poor thermal stability and poor weather resistance, and will age if exposed to the atmosphere for a long time. The mechanical properties of polyformaldehyde are quite good. It has a high strength, elastic modulus, small friction coefficient and good wear resistance. Polyoxymethylene is also highly resistant to creep and stress relaxation. POM has good dimensional stability and very low water absorption, so the impact of water absorption on its mechanical properties can be ignored. Polyoxymethylene has good dielectric properties, and its dielectric constant and dielectric loss tangent change very little over a wide frequency and temperature range. Polyformaldehyde has poor heat resistance and is easily degraded to release aldehyde at the molding temperature. Stabilizers are generally added during granulation. If not stressed, polyoxymethylene can be used at 140°C for short periods of time, and its long-term use temperature is 85°C. Polyformaldehyde has poor weather resistance, and its general performance declines after atmospheric aging. However, its chemical stability is very superior, especially to organic solvents, and its dimensional changes and mechanical property reduction are very small. However, it has poor corrosion resistance to strong acids and strong oxidants such as nitric acid and sulfuric acid. Nylon 66 is polyhexamethylene adipate. Thermal properties (1) Melting point (Tm) The melting point is the temperature when crystallization melts. For crystalline polymer nylon-66, it shows a clear melting point. According to the test method used, the melting point is 259 Fluctuates within the range of ~267℃. The melting point of nylon-66, usually measured by differential thermal analysis (DTA), is 264°C.
In fact, the melting point of nylon-66 can be calculated based on the heat of fusion (ΔH) and melting entropy (ΔS) of crystallization: The ΔH of nylon-66 is 4390.3J/mol, ΔS is 8.37J/kmol, and the theoretical value of Tm is 259.3 ℃[ ]. If the temperature at which the volume expansion coefficient shows a maximum value is regarded as the melting point, the melting point temperature range of nylon-66 is 246~263℃. Close to the theoretical melting temperature of 259°C. (2) Glass transition temperature (Tg). The temperature characteristic values ??such as specific volume and specific heat capacity of polymers can change irregularly at a certain temperature. This temperature is the glass transition temperature, which is when the segments of the molecular chain overcome the intermolecular force. The temperature at which movement begins. Around this temperature, the modulus, vibration frequency, dielectric constant, etc. also begin to change. The glass transition temperature of nylon-66 is related to the testing method, moisture content in the sample, monomer concentration, crystallinity and other factors. Wilhoit and Dole et al. analyzed the temperature change of specific heat capacity and believed that the glass transition temperature of nylon-66 is 47°C[ ], while Rybnikar measured the specific volume of nylon-66 at low temperature and found that nylon-66 also has a specific volume at -65°C. A transition temperature [ ]. Crystallization and Crystallinity (1) Crystal Structure Bill believes that the crystal form of nylon-66 has two forms: α-type and β-type. It is a triclinic crystal at room temperature and a hexagonal crystal above 165°C [ ]. Bunn et al. determined the crystal structure of nylon-66α type [ ], as shown in Figure 01-72, and the lattice constants of its unit cells are listed in Table 01-73. It can be seen from Figure 01-72 that the methylene groups in the nylon-66 molecule are arranged in a zigzag planar shape, the amide group adopts a trans planar structure, and the molecular chain is elongated straightly. Adjacent molecules are connected by hydrogen bonds to form a planar sheet. The model is shown in Figure 01-68. Table 01-68 Lattice constants of nylon-66 stable crystal form Crystal a b c (fiber axis) α β γ α type crystal (triclinic system) 4.9×10-4μm 5.4×10-4μm 17.2×10-4μm 48?° 77 ° 63?° Calculated density = 1.24g/cm3 Figure 01-44 Alpha crystal structure of nylon-66 [ ] Figure 01-4...>>
Question 4: What is polyamide What? There are many varieties of PA, including PA6, PA66, PAll, PAl2, PA46, PA610, PA612, PAl010, etc., as well as many new varieties such as semi-aromatic nylon PA6T and special nylon developed in recent years. Nylon-6 plastic products can use metallic sodium, sodium hydroxide, etc. as the main catalyst, and N-acetyl caprolactam as the co-catalyst, so that δ-caprolactam can be produced directly in the model through negative ion ring-opening polymerization, which is called cast nylon. This method facilitates the manufacture of large plastic parts. Performance: Nylon is a tough angular translucent or milky white crystalline resin. As an engineering plastic, the molecular weight of nylon is generally 15,000-30,000. Nylon has high mechanical strength, high softening point, heat resistance, low friction coefficient, and wear resistance. Self-lubricating, shock absorbing and sound attenuating, oil resistant, weak acid resistant, alkali resistant and general solvent resistant, good electrical insulation, self-extinguishing, non-toxic, odorless, good weather resistance, poor dyeability. The disadvantage is that it has high water absorption, which affects the dimensional stability and electrical properties. Fiber reinforcement can reduce the water absorption of the resin, allowing it to work under high temperature and high humidity. Nylon has a very good affinity with fiberglass. Polyamide is mainly used for synthetic fibers. Its most prominent advantage is that its wear resistance is higher than that of all other fibers. It is 10 times more wear-resistant than cotton and 20 times more resistant than wool. Adding some polyamide fiber to the blended fabric can Greatly improves its wear resistance; when stretched to 3-6%, the elastic recovery rate can reach 100%; it can withstand tens of thousands of bends without breaking. The strength of polyamide fiber is 1-2 times higher than cotton, 4-5 times higher than wool, and 3 times stronger than viscose fiber. However, polyamide fiber has poor heat resistance and light resistance, as well as poor retention, and the clothes made from it are not as crisp as polyester. In addition, nylon-66 and nylon-6 used for clothing have the disadvantages of poor hygroscopicity and dyeability. For this reason, new varieties of polyamide fibers have been developed - new polyamide fibers of nylon-3 and nylon-4, which have high quality. It is light, has excellent wrinkle resistance, good breathability and good durability, dyeability and heat setting, so it is considered to be very promising.
Because polyamide is non-toxic, lightweight, has excellent mechanical strength, wear resistance and good corrosion resistance, it is widely used to replace copper and other metals in the manufacture of bearings, gears, etc. in the machinery, chemical, instrumentation, automobile and other industries. Pump blades and other parts. Polyamide has high strength after melt spinning into filament. It is mainly used as synthetic fiber and can be used as medical suture. Nylon can be blended or purely spun into various medical and knitted products for civilian use. Nylon filaments are mostly used in the knitting and silk industries, such as woven singles, elastic nylon and other wear-resistant nylon socks, nylon gauze, mosquito nets, nylon lace, stretch nylon outerwear, various nylon silks or interwoven of silk goods. Nylon staple fiber is mostly used to blend with wool or other chemical fiber wool-type products to make various wear-resistant and durable clothing materials. In industry, nylon is widely used to make cords, industrial fabrics, cables, conveyor belts, tents, fishing nets, etc. Mainly used in national defense as parachutes and other military fabrics. Polyamide is a type of polymer in which the repeating structure in the molecular chain is an amide group. Polyamide resin is a chemical raw material with excellent performance and wide application. It can be divided into two categories according to its properties: non-reactive or neutral polyamide and reactive polyamide. Neutral polyamide is mainly used in the production of inks, heat-sealing adhesives and coatings, and reactive polyamide is used in epoxy resin curing agents, and in thermosetting surface coatings, adhesives, lining materials, canning, and molding. resin. Neutral dimer acid polyamide resin has good adhesion on polyethylene and other substrates, and is especially suitable for printing on plastic films such as polyethylene surface packaging film and metal foil composite laminated film; inks prepared with neutral polyamide resin are Glossy, good bonding performance, excellent alcohol dilution, low gelling, quick drying, low odor. Dimer acid-based heat-sealing resin is widely used in shoemaking, canning, packaging and book binding; used for edge seam sealing of can packaging; used for bonding new structural containers for frozen apples, oranges and other juices. Thermal sealing polyamide adhesive is used for strong object bonding because it is resistant to dry cleaning, strong detergents, bleaches, and high-temperature washing conditions in laundry rooms and households. It has high adhesion strength to fabrics and is easy to use. It has the necessary It is used in heat shrinkable cable covers due to its adhesion and excellent moisture resistance. Other uses of neutral polyamine resins include the preparation of thixotropic coatings, civil water-based glues, fabric antistatic agents, transparent candles and detergents. The reactive polyamide resin further reacts and is used as a curing agent for epoxy resin, resulting in extensive cross-linking to become a thermosetting resin. When used as a curing agent, it has the advantages of being freely formulated, non-toxic, able to be cured at room temperature, and soft and not brittle, making the epoxy resin extremely...>>
Question Five: Polyvinyl alcohol and acrylamide Polyvinyl alcohol and acrylamide What do you want to ask?
Question 6: Which material is better for making gears, polyethylene or polyamide? Commonly used plastic gear materials are polyacetal and polyamide.
Question 7: What is the difference between polyethylene wax and polyamide wax? What are the prices of 201P and 6900 in the market? Polyamide wax is a low molecular weight wax produced by the polycondensation reaction of dibasic acid and diamine, and is a slurry produced through low-temperature activation. Polyamide wax is rich in hydroxyl and amide groups, which can form strong hydrogen bonding chemical forces and form a network structure, thereby increasing the viscosity of the system to prevent settling and sagging. Each polyamide wax is entangled with each other to form a needle shape. When external stress is applied, the network structure breaks into individual needle-like independent structures. When the external stress or shear force disappears, they form a twisted network structure again.
Polyethylene wax slurry is a pre-gel made from modified polyethylene wax through swelling and cooling. Polyene wax slurry is a colloid that deflocculates through high shear force to achieve an activated and dispersed colloid state. Its advantages are that it prevents hard precipitation, has little impact on gloss, has good viscosity stability, and is not sensitive to temperature. Why is it sensitive
Polyethylene wax is generally oxidized polyethylene wax, which makes the originally non-polar polyethylene carry carboxyl groups, carbonyl groups, etc., thereby forming the necessary conditions for hydrogen bonds.
< p> Question 8: What are the main components of plastics and what role do they play? Plastic component analysis is commonly used in formula analysis, industrial diagnosis, element/ion analysis, purity analysis, etc. Plastic products are widely used in food packaging because of their convenience and low price. Statistics show that plastic packaging accounts for more than half of food packaging.Plastic products used for food packaging mainly include polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polypropylene (PP) and polyamide (P8). Composed of single material and composite material. Although relevant regulations and standards have been issued, there are still food plastic packaging products using harmful additives and inferior recycled materials on the market. Therefore, it is imperative to carry out research on identifying the components of plastic packaging materials for food. This work utilizes ATR. The FT melon method focuses on the qualitative identification of ingredients in a large number of commercially available plastic products for food packaging.
Question 9: What materials can be added to make polyvinyl alcohol and polyacrylamide into glue? Acrylamide is a monomer. It can be added after it is dissolved, and then an initiator can be added for polymerization. However, it cannot provide strength and really works. It's still polyvinyl alcohol.