What are EVA, EAA, EEA, EMA, EMMA, follow me to understand.

EVA

EVA is ethylene-vinyl acetate copolymer, a typical random copolymer. Because EVA introduces a short branch chain composed of polar acetic acid groups into the ethylene branch chain, it disrupts its original crystallization state, thereby reducing the crystallinity of ethylene on the branch chain, and also increases the distance between the polymer chains, which makes EVA more flexible and elastic than polyethylene.

The melt index (MI) of EVA is related to the polymerization process conditions and VA content. Under the same polymerization conditions, if VA content is higher, MI is also higher. The permittivity and the tangent value of the dielectric loss Angle of EVA have a linear function relationship with the VA content in the copolymer, that is, the higher the VA content, the greater the permittivity. The thermal decomposition temperature of EVA is 229℃ ~ 230℃, and it has also been reported that it is above 250℃. EVA is more permeable to gas and moisture than low-density polyethylene, so it is not suitable for highly impermeable materials. The oil and chemical resistance of EVA is slightly worse than that of polyethylene and polyvinyl chloride, and this tendency becomes more obvious with the increase of VA content.

EVA Using:

1, Eva material is an extremely common material, is a more common class of bottom material in daily life, the finished product made of it has good softness, shock resistance, non-slip, strong pressure resistance, such as our common EVA slippers, cotton shoes, EVA mobile phone protective cover, EVAipad protective cover.

2, polymerization method with high pressure bulk polymerization (plastic), solution polymerization (PVC processing AIDS), emulsion polymerization (adhesive), suspension polymerization. Emulsion polymerization was used when the content of vinyl acetate (VA) was higher than 30%, and high pressure bulk polymerization was used when the content of vinyl acetate was lower.

3, EVA sole refers to the sole made of EVA material. EVA sole resilience and high tensile resistance, high toughness, has good shock, buffer performance, heat insulation, heat insulation and low temperature performance is excellent, can withstand cold and exposure to the sun, closed hole, sound insulation effect is good, closed hole structure, no water absorption, moisture, water resistance, salt water, grease, acid, alkali and other chemicals corrosion, antibacterial, non-toxic, tasteless, pollution-free.

EAA 

EAA is ethylene-acrylic acid copolymer, its molecular structure is characterized by the random distribution of carboxyl groups along the main chain and branch chain of ethylene, it is easy to combine with polar substances, so it can provide excellent adhesion and toughness.

EAA has the following characteristics:

(1) Excellent adhesion to metal foil, paper, nylon, polyolefin, glass and other substances;

(2) Excellent corrosion resistance to oil, fat, acid, salt and other chemical products;

(3) The inclusion has good heat sealing property;

(4) Low temperature heat sealing is good;

(5) Good toughness;

(6) not affected by humidity;

(7) Machinability similar to LDPE;

(8) There is a certain corrosiveness and high temperature gelatinability, so after production, the application of LDPE to clean the extruder and can not stay in the barrel to shut down, otherwise it can not be extruded when the next boot, the barrel and screw will be corroded. EAA is commonly used in the manufacture of plastic composite films, toothpaste tubes, cables, antennas, etc., and is currently the most used bonding layer resin.

EAA Using:

EAA is widely used in packaging, powder coatings, adhesives, hot melt adhesives, sealing materials, water based solvents and so on. A brief introduction to the following: 1. Polymer modification 2. Hot melt adhesives and sealants 3. Flexible hoses and ordinary piping 4, laminate 5, multilayer films, injection molded and extruded parts 6, wire and cable mixtures.

Performance Notes: Excellent thermal stability, excellent coloring ability and adhesion to a variety of substrates including metals, polyolefins, cellulose, polyester, polycarbonate, polyvinylidene chloride (PVDC), glass and metal foils. Mainly used in packaging, powder coatings, adhesives, hot melt adhesives, sealing materials, water-based solvents, environmental degradation materials and so on.

EEA

EEA is ethylene-acrylate copolymer, has better toughness than EAA, softness, bending resistance and high temperature thermal stability, and no corrosive degradation products, extrusion composite with PP, PE has a good adhesion, its processing and LDPE approximate, often used to make plastic composite film, but its adhesion with metal foil is not good enough.

EEA resin is the largest polyolefin in toughness and flexibility. Compared with EVA (ethylene-vinyl acetate grease), the same ethylene copolymer, EEA has higher thermal stability, and is a non-corrosive degradation product, so it can adapt to a wider range of processing. EEA is also a thermoplastic with lower crystallinity than PE.

EEA resin is produced by free radical polymerization in a specially modified high-pressure polyethylene reactor. When the content of ethyl acrylate (EA) is increased, the copolymer will become tougher, softer, and more elastic. The polarity of the high ethyl acrylate content resin increases the ability of the surface to absorb ink and has bonding properties.

The density and softness of the copolymer increase with the increase of EA content. EEA polymer has good low temperature performance and softness, good thermal stability during processing, large packing receptivity, excellent resistance to bending cracking and environmental stress cracking, and greater elasticity. The crosslinking of EEA and organic peroxides can improve the heat resistance, creep resistance and solvent resistance.

When the content of ethyl acrylate (EA) increased, the upper limit temperature of the copolymer decreased slightly, and the transparency decreased.

EEA is more widely used in food packaging than EVA, POE, EAA and other polyolefin resins.

EEA Using:

1. EEA is used as flexible, folding and flexible hose, low temperature sealing ring, communication cable semi-conductive sleeve, surgical bag, surgical gloves, packaging film and container, etc.

2, EEA can be used for high temperature extrusion coating (good adhesion to the matrix material) and other plastics low temperature impact resistance and environmental stress cracking resistance modifier.

3, EEA can be involved in carbon black to make conductive materials.

4, EEA can be injection molded car driving disk and other parts, motor parts, safety equipment, cold storage tray, household goods, sports soles, etc.

5. EEA can hollow form various oil and drug containers.

6, EEA can be coated products and laminated products can be used for a variety of packaging materials, metal coating.

7, EEA can be used as electrical insulation materials, shrink packaging film, shrink pipe, composite film and foam.

EEA is more widely used in food packaging than EVA, POE, EAA and other polyolefin resins, and the EA content can not exceed 8% of FDA regulations.

EMA 

EMA is a high polymer material made of ethylene and methyl acrylate as raw materials and oxygen or peroxide as initiators.

EMA can be used as a matrix resin for the masterbatch by adding more than 50% filler without affecting its elasticity and is compatible with all polyolefin resins.

In the case of aseptic packaging using hydrogen peroxide sanitary washes, EMA has also been approved as heat sealing and food surface contact materials, which also meet the requirements of the USP Class VI standard for pharmaceutical use.

EMA resin, when incinerated, does not release undesirable substances such as halogens.

EMA films have a higher surface turbidity than the typical homopolymer LDPE, as well as their latex-like softness, making them suitable for use in disposable gloves and certain medical supplies.

EMA is a good extruded and extruded laminate resin due to its natural good thermal stability, adhesion to common substrates, hot melt and RF welding properties, and can be processed on devices designed for LDPE.

EMA resins are often co-extruded with ring and flat film dies to form a hot melt bonding layer on the substrate.

EMA Using:

EMA is a copolymer of ethylene methyl acrylate. Due to its unique chemical structure, it has the following advantages:

1. Excellent thermal stability

2. Excellent fillability

3. Excellent flexibility and elasticity

4. Good polymer compatibility

5. Excellent seal tear and low temperature heat sealing

 Application

1. Packaging material

As an extrusion coating resin, EMA has good adhesion with PE, PP, PA, PVDC and other substrates, providing an excellent balance between the co-extruded interlayers of LDPE and EVA and the adhesion of the substrate surface. It is widely used in food packaging such as sour milk cup lid, convenient noodle bowl lid and other easy to tear film and multi-layer co-extruded packaging.

2. Medical and sanitary products

As a blowing film resin, it is widely used in the production of soft elastic film, low melting point packaging bags, disposable gloves, medical disinfection covers and so on.

3. Polymer modification

It can be used as a room temperature toughening agent for ABS, PA, PC, PBT, PET, PBT/PC, PC/ABS, PP and other polymers

4. Car soundproofing material

Can be used to produce foaming materials, with uniform foaming, soft, high temperature resistance and other characteristics, can also be cross-linked; The foaming properties of PE and PP can be improved by blending with PE and PP.

EMAA 

EMAA is a copolymer of ethylene-methacrylic acid, similar in chemical properties to EAA, with extremely low degree of crystallization, very good transparency, toughness, elasticity and softness, and excellent adhesion with metal foil, often used in aluminum foil extrusion composite.

EMAA, also known as sarin resin (Surlyn resin), is a copolymer made by the United States DuPont Company using high-pressure free radical polymerization of ethylene-methacrylic acid copolymer through partial or full neutralization.

With an acid content of about 6% (mole) and a density of 0.93 to 0.94 g/cm ³, Surlyn resin can be blown and extruded like low-density polyethylene, and on the other hand, it has higher strength, oil resistance and bond to the material than low-density polyethylene, which was once called transparent polyethylene because of its excellent transparency.

Sarin resin has the following characteristics:

(1) Excellent low temperature impact toughness;

(2) Excellent wear and scratch resistance;

(3) Excellent chemical resistance;

(4) Transparent, clear, luster soft and luxurious;

(5) Excellent melting strength (no fracture under melting tensile);

At present, sarin resin mainly has the following applications:

(1) Cosmetics: perfume bottle caps, cream/cream containers, etc.;

(2) Consumer goods: all kinds of handles, toys, ice buckets, floors;

(3) Sports equipment: golf ball shell, surfboard, snowboard surface, ski boots, skating boots, snowball helmet, shoe heel lining, rodeo protective vest;

(4) Other fields: buoys, outdoor safety lighting, glass products surface coating, pipe screw protection cover, fluorescent lamp surface protection;

EMMA 

EMMA is the English abbreviation of ethylene-methyl methacrylate copolymer, which has more methyl groups on the side chain than EMA in molecular structure, and is a relatively new copolymer. Compared with traditional EEA and EVA, EMMA has many outstanding advantages.

EMMA can be in direct contact with food, and its health and safety performance has passed the FDA certification and the health certification of the Ministry of Health and Welfare of Japan.

In addition, EMMA also has the characteristics of thermal stability, good adhesion, thermal viscosity, low temperature heat sealing, etc.

These characteristics make EMMA widely used, including:

(1) Multi-layer composite film: improve the composite strength of PET, PA and substrate;

(2) Easy to open sealing cover material: PP cup and sealing cover material easy to tear and can meet the requirements of the sealing strength;

(3) high-speed packaging film: packaging hot products to improve yield and production efficiency;

(4) ultra-low temperature heat sealing film: it also has high heat sealing strength;

(5) halogen-free flame retardant cable material substrate: good inclusion of inorganic substances, good processability and surface properties;

(6) The substrate of the shielding layer in the cable material: it will not corrode the metal conductor.