When using butyl tape for construction, sometimes you will encounter such a problem. After heating, the extrusion is not smooth and it is easy to break the glue (broken line). The reason for this problem is that the temperature control of butyl tape during extrusion is not suitable, which directly affects the rheological state of butyl tape during the entire processing process, thereby affecting the quality and aesthetics of the product. what?
The key to the use of butyl tape is extrusion. The temperature control is very important in the extrusion process. Whether the temperature control is appropriate or not directly affects the rheological state of the butyl tape throughout the processing process and affects the inherent quality and beauty of the product. Special attention should be paid to the temperature. Excessive temperature will cause the sealant to melt too much, without strength or even molding (flow phenomenon); too low temperature, the fluidity of the glue is poor, the machine can not squeeze the glue, affecting the construction schedule, which is the main reason for the extrusion . Another reason may be that the butyl tape is mixed with bubbles in the manufacturing process, causing breakage during the extrusion process.
Solution: The selection of temperature is generally based on the extrusion temperature range provided by the manufacturer. The temperature of the extruder is generally set between 110-130 ° C for the barrel and 112-132 ° C for the head. In order to make the host produce a certain pressure and extrude the melt uniformly, the temperature of the head is required to be higher than the temperature of the barrel. The temperature has a certain hysteresis. During the adjustment, it should be noted that the heating and cooling should be carried out gradually. Before the coating is started, the air should be properly exhausted to reduce internal bubbles and voids and prevent bubbles from being generated due to bubbles during extrusion. This is how butyl tape breaks.