New Light Stabilizer for Automotive PP

A new type of light stabilizer, a high-efficiency polypropylene weather-resistant additive, provides long-term weather protection for home-appliance and automotive PP interior and exterior trim parts, and effectively solves the problems of caking, surface bloom and whitening of low-molecular-weight HALS products carried in PP during transportation and storage.

[Aging Performance Evaluation]

Case 1

Test standard: PV 3929:2008 (Aging of non-metallic materials under dry, hot climate conditions)

Test items: xenon-arc accelerated weathering, color difference, gray scale

Main equipment: ATLAS CI3000 water-cooled xenon-arc weathering chamber (USA), CR-10 color-difference meter

Test environment: temperature: (23±2)°C, humidity: (50±10)%RH

Test conditions: irradiance: 0.66 W/m²/nm (340 nm)             black-panel temperature: (90±2)°C

Chamber temperature: (50±2)°C                       relative humidity: (20±10)%

          continuous light, no rainfall

Aging time: 3000 h

Test formulation: UV + 0.3% antioxidant + PP + 30% talc

Remarks: gray scale: 4-5; all samples free of cracking, bloom and chalking.

Tiangang light stabilizer provides better color protection for filled black PP.

Case 2

Test standard: relevant provisions of ISO 4892-2

Test items: xenon-arc accelerated weathering, color difference

Main equipment: Q-Lab Q-Sun Xe-3 air-cooled xenon lamp (USA), CR-10 color-difference meter

Cycle: 3.8 h light/62°C, 1 h condensation/38°C

Irradiance: 0.55 W/m² @340 nm           temperature setting: 62°C light, 38°C dark

Aging time: 1500 h

With the rapid development of the automotive industry, the durability and reliability of automotive parts have received widespread attention. PP (polypropylene), as an important automotive part material, has excellent properties and a wide range of applications. However, PP is prone to aging under light exposure,
which limits its service life. Therefore, the development of new light stabilizers is of great significance for improving the performance of PP automotive parts. This article introduces a new type of light stabilizer specifically for automotive PP and its application in PP materials.

II. Synthesis and Characterization of the New Light Stabilizer

The new light stabilizer introduced in this article is synthesized based on benzotriazole compounds. By introducing specific functional groups, its compatibility with PP materials is improved, thereby enhancing the light stabilization effect. The synthesis steps of the new light stabilizer are as follows:

1. Using benzotriazole as the raw material, introduce the first functional group to obtain intermediate A;

2. Using intermediate A as the raw material, introduce the second functional group to obtain intermediate B;

3. Using intermediate B as the raw material, introduce the third functional group to obtain the new light stabilizer.

The new light stabilizer was characterized by proton nuclear magnetic resonance (¹H NMR), infrared spectroscopy and thermogravimetric analysis. The results show that the structure of the compound is consistent with expectations and its thermal stability is good.

III. Application Research of the Light Stabilizer in PP Materials

The new light stabilizer was added to PP materials, and PP composites were prepared by melt blending. The light stabilization effect of the new light stabilizer on PP materials and its influence on material properties were studied. The results show that after adding the new light stabilizer,
the aging rate of PP materials under UV exposure is significantly reduced, and the mechanical properties and thermal stability of the materials are significantly improved. In addition, the new light stabilizer has good compatibility with PP materials and shows no obvious migration.

IV. Conclusion

In this paper, a new type of light stabilizer specifically for automotive PP was successfully synthesized, and its application in PP materials was studied. The experimental results show that the light stabilizer has excellent UV protection performance and good compatibility, and significantly improves the light stability and durability of PP materials. Therefore, this new light stabilizer has broad application prospects in the manufacture of automotive PP parts. The research in this paper provides a new idea and method for the development of high-efficiency and environmentally friendly light stabilizers,
and helps to promote the development of the automotive parts industry.