With the enhancement of environmental protection and energy-saving requirements of modern life, many advanced energy-saving products and energy-saving technologies are gradually applied to the construction industry in China. Thermal insulation (also known as heat cut and cold bridge) aluminum alloy doors and windows have been widely used in new buildings in the "Three North" (northeast, Northwest and North China) winter cold regions with their good thermal insulation performance in the past two years. In 2003, thermal insulation aluminum alloy doors and windows were gradually popularized in South China, because thermal insulation aluminum alloy doors and windows can maintain the cool environment created by indoor air conditioning. For the East China region with high humidity climate represented by Shanghai, in addition to being "warm in winter and cool in summer", the excellent sound insulation effect and anti condensation effect of insulated aluminum alloy doors and windows have also been recognized by the owners and architectural design professionals. Therefore, in the East China region with the most active economy, insulated aluminum alloy doors and windows have become the new selling point of medium and high-end commercial residential and commercial houses. Throughout the first half of 2003, the rapid development of thermal insulation aluminum alloy doors and windows and curtain walls has become one of the highlights of the promotion of new technologies in the door, window and curtain wall industry in China.
Insulation strips' classification
The production and manufacturing process of thermal insulation aluminum alloy doors, windows and curtain walls originated in the 1970s in Europe. It was introduced into the construction industry in China in 2000. Now it has been recognized and popularized by the technical engineers in the door, window and curtain wall industry. As the key component of thermal insulation aluminum alloy doors and windows and curtain walls, the thermal insulation strip also opens a new product field with the application of thermal insulation aluminum alloy doors and windows and curtain walls. Simply put, the heat insulation aluminum alloy is to divide the original integrated profile into two on the basis of the traditional aluminum alloy, and then connect the separated two parts by means of mechanical composite by two heat insulation strips. The use nature of the heat insulation strip determines that it must have high strength and low conductivity at the same time. Otherwise, it will either cause major quality problems in the heat insulation aluminum alloy doors and windows and curtain walls (insufficient strength will cause the heat insulation aluminum profile to break from the connection of the heat insulation strip), or lose the significance of heat insulation (high conductivity will not guarantee the heat insulation effect). Therefore, the material selection and manufacturing process of the heat insulation strip are very critical.
At present, the heat insulation strip market is divided into three levels: one is the imported nylon heat insulation strip (PA66 GF) represented by Tainuo fengbaotai; The second is the domestic nylon insulation strip produced in 2003; Third, domestic PVC insulation strips. Among them, the thermal insulation strip of the third layer PVC material has a great difference with the linear expansion coefficient of aluminum alloy, and its use safety cannot be guaranteed due to its insufficient strength and poor aging resistance. Therefore, it has been eliminated by the European door and window and curtain wall industries. As for the comparison between imported and domestic insulation strips made of Nylon + glass fiber (PA66 GF), the difference and difference are also obvious.