◆ Polypropylene (PP) is more rigid than polyethylene (PE)

 

The flexural modulus of PP is about 1.52Gpa, the PE is only 207MGpa, and the chemical resistance is similar to that of PE. Taking the Ace PP foaming material of Furukawa Electric Co., Ltd. as an example, its mechanical properties such as tensile strength and tear strength are at the highest level of foam, and its compressive strength is lower than that of hard PUR and foamed PS, but higher than soft PUR. , has a medium compressive strength.

 

◆ Polypropylene has a high heat distortion temperature and can be used in high temperature applications.

 

Expanded polypropylene is generally resistant to 130 ° C, which is much higher than the highest operating temperature of polyethylene foam of 80 ° C. Foamed PP is a closed cell structure like foamed PE. Therefore, its thermal conductivity is not affected by moisture, and it is lower than foamed PE and has remarkable heat insulation properties. Therefore, it can be used as an advanced thermal insulation material. .

 

◆ Good low temperature characteristics

 

EPP products exhibit good performance even at -30 °C.

 

◆ High energy absorption

 

Since the EPP product has a special cell structure, it absorbs the escape energy through gas stagnation and compression in the cell, and has excellent pressure-resistance performance. Widely used in automotive bumper energy processing systems and other anti-collision energy absorbing components.

 

◆ Good dimensional and shape stability

 

EPP products will return to their original shape immediately after repeated impact and deflection, without deformation, and have "memory" ability.

 

◆ Suitable for repeated use

 

EPP products have good flexibility and can be used repeatedly and are not easily broken.

 

◆ Light weight

 

EPP products are extremely light in weight and can be used to reduce weight and can be applied to heavy-duty components such as airplanes and automobiles.

 

◆ Has good surface protection

 

EPP products are semi-rigid, have moderate hardness, softness, no scratches, bumps and objects in contact with them, and have good surface protection.

 

◆ Small water permeability and good buoyancy

 

Due to the closed cell structure of EPP, the products have long-term, excellent floatation and low water permeability, and even the brine does not weaken its buoyancy.

 

◆ Good oil and chemical resistance

 

Due to the chemical inertness of EPP, its products are very resistant to oil and chemicals.

 

◆ Reusable environmentally friendly materials

 

Easy to recycle and reuse, easy to decompose, the product does not contain toxic components harmful to the human body, burning does not produce toxic substances.

 

◆ Density and heterogeneity

 

It can be made into EPP products with different density of parts.

 

◆ Good stability and can be used in different environments

 

EPP products have excellent durability, such as resistance to UV exposure, physical damage, extreme temperature (-30 ° C - 130 ° C) wear and other harsh environments.

 

◆ Sound insulation performance is good

 

EPP products have efficient noise isolation.

 

 

three. Application areas of EPP products

 

 

1. Food packaging

 

In the hard packaging market, the PP market has great potential. The density of foamed PP sheets listed abroad is 0.063 g/cm3, and that of ordinary PP sheets is 0.91 g/cm3. With the development of PP foam sheet products, it will undoubtedly strengthen its competitiveness in replacing PET in the food field.

 

Now microwave ovens and microwave foods have entered people's family life, and cross-linked foamed PP sheet thermoformed food packaging containers can be used in microwave ovens due to heat resistance up to 130 ° C, and are resistant to boiling water, high temperature stability, and surface feel. Comfortable, people have a better impression of its environment. For example, thermoformed foamed PP having a density of 0.5 to 0.7 g/cm 3 and a thickness of 0.5 to 1.5 mm is a raw material for producing tableware, beverage cups and the like having high rigidity and good insulation. Foamed PP sheets having a density of 0.2-1.51 g/cm3 and a thickness of 1.0-3.5 mm are used for the production of meat packaging materials, food packaging materials and bottle gaskets.

 

2. Buffer packaging

 

The most important performance required for cushioning packaging is energy absorption. The PP foam molded article can be used to withstand high loads, and its ability to protect against repeated impact is superior to that of expanded polystyrene (PS) molded articles or foamed polyurethane (PUR). Therefore, foamed PP can be used for shockproof buffer packaging of computers, advanced medical instruments, precision instruments, audio-visual materials, cameras, glass ceramics, handicrafts, various household appliances, etc., so as to avoid damage and damage during transportation. Since it can be directly recycled, the soft texture does not damage the surface of the packaged object, and there is a tendency to replace the PS foaming material in the field of electrical packaging.

 

 

 

Daily use box

 

According to statistics, in 1997 , only two products of color TV sets and color picture tubes used PS foam of 20,000 tons. Hotec Folien believes that PP foam discs have a tendency to replace polystyrene molding discs, and users are interested in PP foam sheets that can be applied directly from the crimping rolls to the forming-canning-sealing device. Recyclable foamed PP trays are convenient for handling and transporting fruits and other agricultural products.