Shanghai, September 8, 2020-LANXESS is working to expand the application range of extrusion blow molding, using continuous fiber-reinforced thermoplastic composites under its Tepex brand in the production process. In a feasibility study, LANXESS experts have confirmed that components made of polyamide 6 can be manufactured by blow molding technology, while using Tepex to locally reinforce heavy-duty parts. The research was conducted on an advanced blow molding machine that simulates production at the Technical Center of the High Performance Materials (HPM) business unit in Dormagen. Arthur Rieb, a blow molding expert in the department, explained: “These components have excellent adhesion, which in turn exerts the amazing strength and rigidity of Tepex.”
This process can locally improve the mechanical properties of blow molded components, such as areas subject to high mechanical stress due to impact load or high pressure. Rieb explained: "In addition, it is also suitable for the manufacture of blow-molded structural components, such as hollow profiles for body reinforcement. Widespread use of Tepex is expected to become a key factor in reducing weight and material consumption, and the basic wall thickness of components can therefore be reduced. "Hollow parts based purely on thermoplastic systems are easier to recycle, creating a closed loop of materials.
Engineering plastics experts Tilmann Sontag (left), Loren Winkelhake and Arthur Rieb evaluate the quality of blow-molded Tepex-reinforced hollow parts at the technical center of the LANXESS Performance Materials business unit in Dormagen.
To manufacture such hollow parts, the tubular parison is first pressed, and the heated and plasticized Tepex insert is placed in the blow molding tool. Then, the parison is inflated in the tool, and the Tepex profile is formed, resulting in a component with a predetermined shape and local Tepex reinforcement. "Integrating Tepex molding into the blow molding process makes the overall process in place in one step, short cycle time, and cost-effective, which is a typical blow molding," Rieb added.
Simplify the process
Prior to this, the manufacture of such components required blow-molded hollow parts, followed by welding a two-dimensional or three-dimensional Tepex insert. In the first case, the whole process is divided into two stages, and in the second case, due to the early-stage Tepex molding, the whole process is divided into three stages. Tilmann Sontag, a lightweight design expert in the Tepex Automotive Group of LANXESS` high-performance materials business unit, said: “Therefore, our process makes the entire manufacturing process more convenient. In addition, the fabric reinforcement makes the plasticized Tepex material better than the continuous fiber unidirectional reinforcement. The tape is easier to handle, so it can be produced stably and safely."
With the excellent adhesion between the blow molding material and Tepex, Tepex can give full play to its strength and rigidity advantages in the formed material bonding.
Fully consolidated material bonding
The continuous fibers in Tepex are completely pre-impregnated with plastic. Therefore, the pressure during the blow molding process is sufficient to consolidate the material, thereby avoiding air pockets. "In this way, a material bond is formed between the blow molding material and Tepex, which has excellent adhesion. Even a low blow molding pressure is sufficient for Tepex to form key three-dimensional geometries, such as a hemisphere with a smaller radius." Sontagd said.
A variety of blow moldable polyamide products
LANXESS Performance Materials has developed a series of high-viscosity compounds based on polyamide 6 and 66, with or without glass fiber reinforcement. These materials can also be used in new processes/material combinations. This series also has very soft and impact resistant derivatives, such as unreinforced polyamide 6 compounds (Durethan BC700HTS DUSXBL and Durethan BC550Z DUSXBL). This type of material is extremely suitable for Tepex reinforced storage tanks or other hollow parts that require high impact resistance and flexibility. In contrast, glass fiber reinforced products are often the material of choice for lightweight structural components.
With Tepex, the process can also be used for more product types, such as reinforced material variants, whether the material is a continuous fiber fabric or a laminate made of glass, aramid or carbon fiber. The matrix of the composite material can also be flexible and changeable. In addition to polyamide 6 or 66, it can also be made of polyolefins such as polypropylene or polyethylene.
HiAnt-full service customers
LANXESS`high-performance materials business unit integrates its expertise in materials, applications, procedures and technology development into the HiAnt brand to support customers at all stages of component development, including conceptual design, material optimization, and utilization simulation The tool calculates the component characteristics until the whole process of processing, component testing and mass production.