Shanghai Risheng Technology Co., Ltd.

The development of the wire and cable industry is currently in the transition period from PVC materials to halogen-free environmental protection materials. Environmental awareness has become a worldwide consensus. The United States, Japan, the European Union and other developed regions clearly stipulate that imported wire and cable products must meet the requirements of halogen-free, low toxicity, and flame retardant. It requires that cables have low smoke volume, no or less corrosive gases and harmful halogen gases during combustion., No heavy metals such as lead, no soil pollution, high heat resistance, and recyclable waste wire and cable materials. In particular, the safety of the product, non-toxic, flame retardant and other indicators of special attention. The "de-halogen flame retardant" wave of wire and cable (Cable & wire) is rolling in from the West. Microsoft, Motorola, HP, Nokia, Sony, Samsun, LG and other well-known industrial customers have set a clear timetable for the halogen-free process.

In the context of the acceleration of the halogen-free process, for modified plastic manufacturers and wire rod finished product processors in the development and selection of halogen-free flame retardant TPE should be how to choose? The author from their own experience in the field of TPE, to talk about the current halogen-free flame retardant TPE in the industry present characteristics and common problems, for modified plastic factory and wire rod processing plant to provide research and development and material selection help.

1. High prices

Halogen-free flame retardant TPE products are expensive, more than 5 times that of ordinary PVC. The selling price on the market is between 45-150 yuan/kg. This is due to the large difference in cost due to the different effect flame retardants in the product. The amount of flame retardant in the raw material is large, generally accounting for about 30%-50% of the proportion of the material itself. Flame retardant TPE has extremely strict requirements on formula. For the stability of products, genuine SEBS and pure TPU base materials of super brand producers are often used as preferred materials and are not easy to replace, accounting for about 50%. In addition, flame retardant synergistic agents, lubricants, surface treatment agents are the reasons for its high cost. This has led to many end customers are difficult to immediately completely replace the halogen-free flame retardant TPE reasons. So do halogen-free flame retardant TPE to reduce costs, in the customer to get the actual application is the hard truth!

2. Precipitation of finished product

Another problem of halogen-free flame retardant TPE is that the finished product is easy to precipitate during use. Specific performance in: the surface white, foggy or surface oil, shiny. There is no company in the world whose materials can be guaranteed to be completely unprecipitated, including Ensmann, Nuoyu, Taiwan Rubber and Rubber Treasure. The reason for the precipitation is the imbalance between macromolecules and small molecules in the formulation system, and after a period of time, the movement of macromolecules causes small molecules to migrate to the surface. So far, the prior art has not completely solved this problem. It is suggested that customers should choose materials with slightly white surface when choosing, which will not affect its physical and electrical properties.. In addition, according to the quality of the flame retardant system in the formula, the precipitation also has the weight, the good material precipitation is less, and it is not easy to happen in the short term. Therefore, in the selection of TPE, we can not completely pursue the price and ignore the quality.

3. Subsidiary Performance Concerns

When choosing halogen-free flame retardant TPE, in addition to focusing on his flame retardant and appearance properties, some properties are often ignored by us. For example, insulation resistance, aging temperature resistance, thermal shock, voltage resistance, pressure cracking, heating deformation, etc. These performances are often not up to standard. These performance does not meet the standard is often due to the choice of raw materials and processing methods in the formulation.

Raw materials are likely to be manufacturers in order to save costs with relatively poor raw materials or did not find suitable raw materials. Of course, it is also related to the synthesis technology. If the technology is not improved, the best materials will not meet the standard. There is also great emphasis on processing methods. Screw element arrangement, screw rotation frequency, feeding speed and processing temperature are all related to the dispersion of rubber particles in the system. The dispersion of rubber particles is directly related to all aspects of mechanical properties of TPE.

4. TPE printing difficult

Flame retardant TPE printing is very difficult to solve. TPE has different printing effects due to different base materials. TPE polarity is similar to ink, the easier it is to print. TPE based on styrene block copolymer is a non-polar material with poor compatibility with ink and is not easy to print. Therefore, in terms of material selection, more attention should be paid to the base material of TPE itself, and TPE materials containing TPU or polar modifiers can be selected.

5. The surface is tingling and not smooth.

In the injection molding process, TPE this material will often happen this kind of thing. Generally, it is caused by the temperature not being adjusted well and the washing machine not being clean. It is also possible that the die head and eye mold are deformed, there are foreign bodies, and it is also possible that the mold is not selected correctly. Of course, this is also related to the manufacturer's formula. The formula system has good compatibility and uniform distribution, and the less obvious this phenomenon is. The greater the hardness of the TPE, the greater the viscosity of the TPE.

6. Swing and bonding

The wire swing test is to detect the bending degree of the wire, whether there is false soldering at the solder joint, the open circuit of the line, and the short circuit between the line and the line. There are many standards for swinging, mainly depending on the structure of the wire itself, which has little to do with the external material. Generally, it is enough to adjust the twisting moment of copper wire. Of course, a good external material can still play a certain role in anti-sway damage. Poor bonding is mostly caused by the large difference in material solubility parameters between the plug part and the wire part when bonding, and the difference in polarity. When selecting materials, attention should be paid to selecting TPE similar to the polarity of the plug material.

In short, flame retardant TPE is a very unique material. It is normal for high-end products in the market, such as Nokia, Sony Ericsson, Motorola, LG, Mingji, HP, Microsoft and other large companies' earphone lines, charger lines and computer peripheral lines, to use halogen-free flame retardant TPE. Power lines, military lines, nuclear lines, slingshot lines, car lines must also be adjusted. In the future, more wires in the middle and low-end markets will also change their materials in the current field according to the laws and regulations of European and American countries. It can be predicted how large this market is, and it can also be imagined that halogen-free flame retardant switching is inevitable. Environmental protection is the future trend. Therefore, the development of halogen-free flame retardant TPE materials with lower prices and better overall performance requires the joint efforts of major modified plastic factories and wire rod manufacturers, upstream and downstream, so as to make our entertainment and life safer and more environmentally friendly.