How to choose the raw materials and accessories for packing

Different grades of polypropylene (PP) have a great influence on the melt flow properties and processability of materials due to their different molecular weights and molecular weight distributions. Properties such as tensile strength and elongation, etc., have a rise in molecular weight. The high tendency of molecular weight and molecular weight distribution has a great influence on the extensibility of fibers, so different grades of PP are selected for different uses and processing methods.

In order to ensure that the produced PP strapping belt has excellent properties such as high tensile strength and good elasticity, it is necessary to select a suitable melt index PP resin as raw material. The production of packaging belts for PP machine is generally mixed with PP filling masterbatch. APP-filled masterbatch is one of them, its main components are atactic polypropylene and CaCO3, and its characteristics are as follows:

The addition of APP masterbatch has the effect of plasticization, elasticity, and moisturization, which makes it easier for PP macromolecule bonds to align in the stretching process, and can increase the pull strength and other physical and mechanical properties of the packing tape, but APP is added. To a certain extent, the rigidity of the product is affected. When the amount exceeds a certain amount, the production process is significantly changed, the temperature of the die is lowered, and the discharging of the material is accelerated, which may cause the product rigidity to decline to affect the product quality. Therefore, the application of APP in PP should pay attention to the appropriate amount, generally accounting for 10% is more appropriate, so that on the one hand to improve the process conditions (operating temperature, extrusion speed), on the other hand to improve product quality.

When the strap is used, the joint of the manual strap is sleeved with iron clips and forcedly clamped with the pliers. The strapping of the machine is made by hot melt bonding the two connectors, and its fastness directly affects the packaging. quality. Lapping is the maximum tensile force that can be sustained when the belt is broken. Generally, it can meet the requirements of 80 to 150 kg. The normal working temperature of the mechanical baling press is 90-220°C. In this condition, whether the packing tape after the adhesion meets the requirements or not, and the rational use of the baling press is mainly controlled by the packaging belt production process. In order to increase the contact area of ​​the two belts during hot-melting, the machine-packaging belts should use smaller diamond-shaped ginning patterns. The amount of APP filler added also directly affects the lap tension. With a large amount of APP, it will not be as strong as the lap of the pure PP hot melt. The amount of APP should be about 10%.

As a professional plastic packaging manufacturer, Wuhan Eimetech has developed high-end, mid-to-low-end various packaging belts that are most suitable for the market with its many years of experience in plastic packaging production. The products include PP packaging belts, PET plastic strapping belts, and strapping ropes. Products to meet customer choices for different investment scales. Ai Mei Jie warmly welcomes friends and colleagues at home and abroad to communicate and cooperate with us. We will make friends with you with the unique passion of Wuhan people.