Application of Halogen Free Flame Retardant PC/ABS in Mobile Phone Case

First, the general requirements of mobile phone shell materials

High strength, good heat and thermal conductivity, flame retardant, and battery shielding.

Stable size, good appearance, and light weight and thin wall.

Currently, the materials commonly used in mobile phone cases are PC , ABS and PC/ABS.

Second, the characteristics of different materials and selection principles

1. Characteristics of different materials:

PC

High strength, tensile strength 69MPa, bending strength 96MPa.

High temperature resistance, long-term use can withstand 130 degrees Celsius temperature environment.

Good transparency and non-toxicity.

The color matching and surface coating of raw materials are not as good as ABS.

The PC should choose a high liquidity grade.

Suitable for clamshell machines and mobile phones used in harsh environments.

ABS

Low strength, tensile strength 43MPa, bending strength 79MPa.

Not resistant to temperature, the long-term use temperature must not be higher than 60 degrees Celsius.

Fluidity, coloring and surface coating and plating properties are good.

PC/ABS

The synthetic materials of PC and ABS take the characteristics of the former two, have excellent molding processing performance, good fluidity and high strength (wearing strength 56MPa, bending strength 86MPa). PC/ABS materials are mainly used for straight-plate machines and clamshell machines with general appearance, high color requirements and no special requirements on the environment.

2. Material selection principle:

According to the structure selection

PC/ABS should be preferred when the structure is strong, the wall is thick, and the structure is complex.

When the structure is thin and the strength is insufficient, the PC should be selected.

Color selection according to the appearance of painting:

When the color is bright, multi-color, and strict requirements are imposed on the equipment, PC/ABS should be preferred.

When plating is required for appearance, ABS should be selected. PC materials should be used for clamshell machines and ruggedized mobile phones used in harsh environments such as low temperatures, vibrations, shocks, etc. Straight machine selection: When PC and PC/ABS can be used, PC/ABS should be preferred.

Third, the mobile phone shell material new noble halogen-free flame retardant PC / ABS

With the popularity of straight-bar machines, PC/ABS has become a common choice for mobile phone casings. However, with the advancement of technology, people's calls for safety and environmental protection are increasing, and the requirements for flame retardant properties and environmental friendliness of materials are getting higher and higher. . At present, halogen-based flame retardants such as decabromodiphenyl ether are commonly used in the thermal cracking and burning of materials to produce toxic, corrosive gases and a large amount of smog, which pollute the environment and cause secondary pollution. The EU introduced ROHS and WEEE in 2003. The promulgation of the two directives has limited the application of traditional halogen-based flame retardant PC/ABS alloys in many industries, especially the restrictions on the use of flame retardants in mobile phone casing materials in Europe and the United States in recent years. Therefore, research and development of highly efficient and environmentally friendly halogen-free flame retardant PC/ABS alloys has become the focus of research in the field of flame retardant.

Commonly used halogen-free flame retardants:

Common methods for preparing flame-retardant engineering plastics include additive flame retardant technology and reactive flame retardant technology. For PC/ABS alloy systems, additive flame retardant technology is widely used at home and abroad. Currently commonly used flame retardants are:

Development trend of halogen-free flame retardant PC/ABS alloy:

With the increasing demand for PC/ABS engineering plastic alloys and increasing emphasis on environmental protection, the development of flame retardant PC/ABS alloys has gradually turned to halogen-free environmental protection, high performance, multi-functionality and systematization. Direction development. At present, halogen-free flame retardants such as phosphorus-based flame retardants and silicon-based flame retardants have broad application prospects in PC/ABS alloys. However, there are still some shortcomings, such as the lack of compatibility with materials, especially the balance of impact strength, flame retardancy and processing properties, still need to be improved, some flame retardants are more expensive. Therefore, in order to meet the requirements of both flame retardant and environmental protection, how to further improve the flame retardant effect of flame retardants and the comprehensive properties of alloys, and develop high-efficiency environmentally friendly flame retardants and functional flame retardant materials (such as biodegradable materials) are currently studied. Hot spots and priorities. It can be seen that new technologies for research and development of flame retardants such as nanotechnology, microencapsulation technology, compounding synergy technology, surface modification technology, and compatible technology will be continuously developed.