Hot melt adhesive industry terms

Hot melt adhesive: A thermoplastic adhesive with polymer as the main body that is coated in a melted state and solidifies after cooling;

Pressure-sensitive adhesive: that is, self-adhesive, the surface is sticky at room temperature, and the substrate can be bonded under pressure;

Polymer: such as rubber, plastic, fiber and other substances with a long chain molecular structure composed of repeated units, also become polymer materials;

EVA: ethylene-vinyl acetate copolymer. It can be used as the basic polymer of hot melt adhesive and is widely used in the manufacture of hot melt adhesive.

TPU: thermoplastic polyurethane. There are polyester type and polyether type, which can be used as the basic polymer for manufacturing hot melt adhesive.

PA: Polyamide, commonly known as nylon. It is a general term for polymers containing amide groups in the main chain repeating unit of macromolecules, and can be used as the basic polymer of hot melt adhesives.

PES: Polyester resin. It is a product of esterification of polyacids and polyols. The polyester used for hot melt adhesive is a thermoplastic product of straight chain molecules obtained by esterification of saturated dibasic acid and dibasic alcohol, and there is no unsaturated carbon-carbon bond in the molecular structure, so it is a saturated polyester.

PO: polyolefin. Common polyolefin are polyethylene, polypropylene and so on;

Viscosifier: reduce the melt viscosity of the hot melt adhesive, improve its wettability and initial viscosity to the bonded surface, in order to improve the bonding strength, improve operational performance and reduce costs. In addition, it can also adjust the heat resistance temperature and drying time of the glue, commonly used tackifier are rosin resin, petroleum resin, etc.

Plasticizer: also called plasticizer, is widely used in the industry of polymer material additives, adding this substance in plastic processing, can make its flexibility enhanced, easy to process. The function of plasticizer in hot melt adhesive is to speed up the melting speed, reduce the melting viscosity, improve the wettability of the bonded material, and improve the flexibility and cold resistance of hot melt adhesive.

Thermoplasticity: The ability to melt and solidify repeatedly under the action of heating and cooling;

Viscosity: An indicator of fluid flow, with high viscosity and poor fluidity. It is related to the properties of the fluid itself, temperature, concentration and so on.

Viscosity: or initial adhesion, refers to the ability to stick to other objects under slight pressure;

Opening time: refers to the longest time interval between the adhesive from coating to the surface can still be glued to the substrate, and the adhesive has the bonding effect within the opening time;

Curing time: the shortest time for the adhesive to be pressed between the two substrates to form a firm bond, and the pressure holding time should not be less than the fixed time to form a good bond;

Cohesion: microscopic term for the strength of a material itself, similar to tensile strength;

Thermal stability: the ability of the material to withstand high temperatures for a long time;

Softening point: The material becomes soft when heated, close to the temperature of flow;

Glass transition temperature: refers to the polymer material from rubber state to plastic state transition temperature. Each hot melt adhesive has a specific

If the glass transition temperature is lower than the glass transition temperature, the hot melt adhesive will lose toughness and viscosity;

Melting point range: refers to the temperature range measured by capillary method from the beginning of the substance to all melting;

Low temperature resistance: the ability of hot melt adhesive to maintain good bond strength or adhesion at low temperatures;

Heat resistance: the highest temperature that the bonding system can withstand under the condition that the bond is not destroyed;

Flame resistance: the ability of a material to resist burning when it comes into contact with a flame or to hinder continued burning when it leaves the flame;

Water resistance: The ability of a material to retain its physical and chemical properties after the action of water or moisture;

Oil resistance: the ability of a material to resist swelling, dissolution, cracking, deformation or reduction of physical properties caused by oil;

The ability to resist swelling, dissolution, cracking, or deformation caused by solvents;

Chemical resistance: The ability to resist acids, alkalis, salts, solvents and other chemicals;

Weather resistance: the resistance of the material to exposure to sunlight, hot and cold, wind and rain and other climatic conditions;

Durability: Durability is also known as stability and service life. That is, the ability to maintain its performance for a long time under the combined action of external environmental factors;

Aging resistance: refers to the degree of bond strength or viscosity change with time during storage of the bonding system at room temperature;

Substrate damage: the substrate is torn and the adhesive and interface cannot be damaged, because the substrate strength is not enough, or the bonding strength is very good;

Cohesion failure: that is, the adhesive is broken, the bond is disconnected from the middle of the glue, and the strength of the glue itself is not enough;

Interface damage: the bonding is disconnected from the interface, the glue and the substrate itself are good, and the affinity of the glue, the surface treatment of the substrate, the coating process, the substrate pollution and other factors are related;