The Application Value of PEG-4000 in Rubber Products
PEG-4000, as a medium molecular weight solid polyethylene glycol, is a commonly used environmentally friendly processing aid in rubber mixing, extrusion, and vulcanization processes due to its moderate lubrication, oil absorption and dispersion, and improved processing flowability. It is widely used in natural rubber and synthetic rubber formulations.
1、 Five core roles in the rubber field
* Internal and external composite lubrication improves processing fluidity
Dual effects of internal and external lubrication: internal molecules penetrate the rubber molecular chain, reducing the melt viscosity of the rubber material and saving time and energy during mixing; A lubricating film is formed on the surface between the rubber material, the rubber roller, and the screw to avoid sticking to the rollers and molds, and to facilitate smooth extrusion and rolling molding. Compared to PEG8000 and 10000, the lubrication is balanced and there will be no frosting caused by excessive molecular weight.
*Filler wetting dispersant
Quickly infiltrate inorganic fillers such as carbon black, calcium carbonate, and white carbon black, break the agglomeration and agglomeration of powder, promote the uniform dispersion of fillers in the rubber matrix, reduce white spots and particle lumps of rubber, and improve the density and mechanical strength of rubber.
* Moisture absorption and anti coking, regulating vulcanization rate
Adsorb trace amounts of moisture and acidic small molecules in the adhesive material, delay local burning, and optimize the uniformity of vulcanization; Assisted by zinc oxide and accelerator dispersion, the vulcanization reaction proceeds smoothly, resulting in uniform thickness and stable physical properties of the finished product.
*Improve the cold resistance and toughening modification of rubber
Moderately improve the low-temperature flexibility of the rubber material, reduce the probability of hard and brittle cracking of the product, and enhance the cold resistance of sealing strips, hoses, and miscellaneous parts; Add a small amount to optimize the extensibility of the adhesive material, making it easy to cut and shape.
*Anti static and improve the surface smoothness of products
Forming a hydrophilic thin layer on the surface of rubber reduces the production friction and electrostatic adsorption of dust, resulting in a smooth and non rough surface of the finished product and optimizing the appearance grade of rubber.
2、 Reference addition amount
Conventional rubber formula: 1.0% to 3.5% (raw rubber mass); The reinforcement system of white carbon black can be increased to 3% to 5%.
3、 Product selection advantages
Compared to PEG6000/8000, PEG4000 has a moderate melting point, moderate mobility, minimal lubrication, and is less prone to oil and frost in later products; Compared to small molecular weight PEG400, it is less prone to high-temperature volatilization and has better sulfurization stability.
4、 Applicable rubber category
Nitrile rubber NBR, natural rubber NR, styrene butadiene SBR, PVC modified rubber, EPDM EPDM sealing strip, rubber hose, rubber sole, sealing gasket.
