Differentiated adaptation of UVLED curing process in plastic bonding
1. PC/ABS: Penetration and Thermal Management of Highly Transmittant Materials
PC (polycarbonate) and ABS (acrylonitrile butadiene styrene) have high light transmittance, but high-power curing can easily induce internal stress. Adaptation solutions include, Light Source Selection: 365nm short-wavelength UV LEDs are preferred, with a penetration depth of at least 2mm to ensure deep curing of the adhesive layer; Power Control: Equipment power density should be ≥1000mW/cm², shortening the curing time to 5-10 seconds to reduce the risk of deformation caused by heat accumulation; Process Optimization: Incorporating a primer-coated light absorber improves the bond between the adhesive and the substrate and prevents interfacial delamination.
2. PP/PE: Surface Modification and Penetration Enhancement for Low-Absorbing Materials
PP (polypropylene) and PE (polyethylene) have dense molecular structures and low light absorption, requiring specific treatments to overcome their surface inertness. Pre-treatment process: Increase surface roughness through plasma treatment or laser etching to enhance adhesive bonding; Long-wavelength light source: Use a 405nm wavelength light source to increase photon penetration into the material, and combine it with a photosensitive primer for uniform curing; Layered curing strategy: First, perform low-power pre-curing (to form a pre-bonding layer), then gradually increase the power to complete the overall curing.
3. TPU/Silicone: Stress Control and Shrinkage Management in Flexible Materials
During the curing process, flexible materials (such as TPU and silicone) are prone to cracking at the adhesive interface due to shrinkage stress:
Pulse-type curing. Use an intermittent on-off mode (e.g., 10ms pulse with 90% duty cycle) to reduce the instantaneous coefficient of thermal expansion: Selection of elastomer adhesive: Use a low-modulus UV adhesive, combined with a flexible optical path design (e.g., a bendable reflective cavity) to accommodate substrate deformation;Gradient power adjustment: Use low power at the initial stage to release stress, gradually increasing to high power at the later stage to ensure complete curing.
4. Process Optimization for Composite Materials
For multilayer or heterogeneous materials (e.g., PC/ABS+PP), process synergy is essential:
Zone-based light source control: Integrate multiple wavelength modules in a single device to independently adjust parameters for different areas;
Dynamic power compensation: Real-time monitoring of curing energy via sensors to automatically compensate for energy attenuation caused by material thickness variations.
In summary, the application of UVLED curing technology in plastic bonding requires a focus on material properties. By optimizing light source parameters, innovating pretreatment processes, and customizing equipment functions, technical challenges such as light transmittance, light absorption, and shrinkage can be overcome. In the future, with advancements in light source power density and the integration of intelligent control algorithms, UVLED technology will further promote the efficient and precise bonding of plastic structural components in industries such as automotive and 3C electronics.
اتصل شخص: Mr. Eric Hu
الهاتف :: 0086-13510152819