[Technology]A summary of the essential problems of elastomers such as TPE rubber coating grindingdamage and scratching, TPR shoe material fabric color migration, etc.
1
– utpe question and answer time-
There are traces of TPE, how to deal with it?
What kind of traces? If it is water marks, you can dry the raw materials; if it is weld marks, you can increase the injection molding temperature; if it is caused by flash, you need to lower the temperature.
2
– utpe question and answer time-
The surface and surface of highly filled TPE/TPR during extrusion How to deal with the different surface density and brightness of injection molding?
This is caused by the different processing temperatures and shear forces of the two machines. The extrusion processing temperature of the same material is generally lower than that of injection molding. Extrusion pays more attention to the melt strength. If the temperature is too high, the fluidity is too good, and the extrusion strength is too low, it will be easily broken by gravity or traction.
3
– utpe question and answer time-
Is it possible that organic tin is in our TPR materials?
Organotin is one of the commonly used stabilizers for PVC, mainly because the processing temperature of PVC exceeds the decomposition temperature, so stabilizers need to be added. The raw materials in TPR do not have this problem, so there is no need to add stabilizers. If organotin stabilizers are detected in the TPR, it may be due to mixing, granulation, extrusion or injection molding equipment.
4
– utpe question and answer time-
The surface of the products made by SEBS is still a little bright. What are some good ways to deal with it?
Made from medium to high molecular weight SEBS, it tends to be matte. For a bright surface, you can choose to use SEBS with medium and high molecular weight, or you can lower the temperature or reduce the lubricant content; you can also reduce the oil filling, but it will increase the cost. If the fluidity is poor, the surface will not be so bright.
5
– utpe question and answer time-
Can TPE be modified by adding TPU? The compatibility should not be good. Is there any similar modifier added?
It is mainly a compatibilizer. Maleic anhydride can be grafted with SEBS. Generally, there are Caton 1901 and Li Changrong 9901. There are also some companies that specialize in grafting materials.
6
– utpe question and answer time-
TPE coating is easy to wear and scratch, what’s going on?
The scratching phenomenon may be caused by the material being filled with more ingredients and the scratch resistance is reduced. The formula can be adjusted to solve the problem. Use coupling agents, compatibilizers, etc. to help disperse, increase the processing temperature and the molecular weight of the rubber used.
7
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How can the TPE surface be very sticky? As sticky as Scotch tape.
Low molecular weight SEBS + tackifying resin (petroleum resin, rosin resin, terpene resin, etc.) are required; if more viscosity is required, some SEBS containing diblocks can be used. You can take a look at the hot melt pressure-sensitive adhesive formula of the SIS/SBS system for reference.
8
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When the customer’s extruder uses the same material to make the wire, a few centimeters of dead glue will appear every few meters apart. However, the results produced by other customers using this material are good and can meet the requirements, and there is no such phenomenon. what happened?
Since other customers have no problem with it, it may be due to this customer’s mold design problem. The dead glue that appears every few meters may be caused by the accumulated material in the mold being brought out.
9
– utpe question and answer time-
The color of the TPR federal shoe material has been migrated by the fabric. Is there any solution?
The color migration is most likely caused by the toner. It is recommended to try changing the toner.
10
– utpe question and answer time-
What is the compatibility between PPO and SEBS?
PPO has good compatibility with the styrene phase of SEBS, so there is no problem.
