Since the end of the last century, carbon fiber rods have become one of the keywords for the application of advanced composite materials. As domestic carbon fiber rod raw material production technology has gradually broken through the international technical blockade, it has achieved T300, T700 and other models of carbon fiber rods. Production capacity.
The application of thermosetting carbon fiber rod composites, especially those based on epoxy resin, has been developed rapidly.
Relatively speaking, the application of thermoplastic carbon fiber rod composites is very limited. Why is the development of carbon fiber rod reinforced thermoplastic composites slow in China? I think there are several reasons.
Firstly, the demand market is not comprehensive enough to understand the thermoplastic carbon fiber rod composites, and the advantages of thermoplastic carbon fiber rod composites are not paid enough attention, thus affecting the normal growth of market demand.
It is generally believed that thermoplastic polymers are inferior to thermosetting polymers in terms of temperature, mechanical properties, creep resistance and aging properties.
In fact, the thermosetting carbon fiber rod composite material is not without its disadvantages. It has a series of weaknesses such as long forming cycle, poor impact toughness, short storage time of preimpregnation material, non-reusable, and difficult to repair local damage.
Compared with the thermosetting resin based carbon fiber rod composites, the thermoplastic carbon fiber rod composites have obvious advantages such as high toughness, high impact resistance and damage tolerance, unlimited preprepreg storage period, short molding cycle, high production efficiency, and easy repair.
The utilization value of thermoplastic carbon fiber rod composites has not been fully understood and developed, which directly affects the production of market demand. The extremely limited demand exists in the high-end small range such as aerospace. From the source of supply and demand, the further development and application of thermoplastic carbon fiber rod composites are hindered.
Secondly, the high technical requirements of thermoplastic carbon fiber rod composite manufacturing technology limit the entry of some enterprises with insufficient technical level and production capacity.
Most thermoplastic resins have high viscosity at melting temperatures and can not be well impregnated with fiber fabrics. Therefore, the preparation of prepreprepreprepregs for thermoplastic resin-based carbon fiber rod composites is very difficult and can not solve the problem of high viscosity of thermoplastic resins., Let's not talk about anything else.
The most commonly used preleaching process for thermoplastic composites is the melting method. The basic processes include fiber lead, wire display, preheating, impregnation, cooling, and winding.
The preparation of thermoplastic carbon fiber rod composite preprepregs by melting method also needs to solve the problems such as hollow dry spots caused by high viscosity and short impregnation time, and the fiber needs to be well and non-destructive dispersion.
Moreover, the high cost of raw materials has led to curtailing downstream application demand. Carbon fiber rod raw wire is expensive, high-end thermoplastic resin is also dozens of times the price of ordinary epoxy resin, coupled with the high technical requirements, a variety of factors, resulting in thermoplastic carbon fiber rod composite material.
In particular, the price of carbon fiber rod composite products using high end thermoplastic resins such as PEEK and PI is daunting. On the other hand, carbon fiber rod reinforced thermoplastic composites used in China mainly rely on imports.
The supply of high-performance thermoplastic composite preprepregs abroad is monopolized by companies such as TenCate, Cytec, and Ticona. These companies have the ability to supply various series of fibre/carbon fiber rods to enhance PEI, PPS, and PEEK thermoplastic prepregs. The price of pre-impregnated materials after being monopolized is naturally high.
The transformation of the achievements in the field of thermoplastic carbon fiber rod composites in China is not smooth. The preparation and research of thermoplastic composite preimpregnates have a certain foundation in China, but it is compared with developed countries.
There are still large gaps, and the lack of continuity of follow-up work, resulting in the current lack of materials preparation and structural molding related key technologies and equipment