High temperature resistant performance is poor, auto polymer materials is another major drawback. Most thermoplastic polymer material working temperature is below 80 degrees Celsius, the temperature is above the thermal deformation often occurs, the polymer can't maintain its original shape and structure, performance changes dramatically, antifreeze performance is poor, a lot of plastic with cold brittleness, mainly in plastic parts in the winter, hit from impact especially easy to cause damage, for this reason to make a lot of plastic in low temperature environment is limited. The shortcomings of thermoplastics can currently by adding other materials in raw materials or additives modified formula composition, make it improve the low temperature impact strength, be combustibility: compared with steel, plastic can be another disadvantage is burning. This is auto polymer materials in recent years one of the most attention to the problems in the process of application, as well as the most don't trust many occasions to use one of the main reasons for polymer materials. Plastics can be divided into two kinds, one kind is not the burning, another kind is to burn. However, because the plastic has the function of combination and formula can be modified to burn in formulated by plastic burning flame retardants and not filling modification, modification, as a flame retardant or non combustible plastic let rest assured use. # 5, ageing resistance performance: the aging properties of plastic are long effect the car another reason of material application development. But, in fact, it should be an objective view on the aging problem of the plastic building materials. Polymer materials should not only consider the heat ageing, consider often contact medium resistance to light aging and aging. Can pass in the formula by adding a variety of inhibitor to prevent aging. Polymer materials with quite a number of advantages, but as a result of the above shortcomings, more still is automotive inner decoration material and car functional products applied to give priority to. With the development of science and technology, more and more new macromolecule material success continuously study, many polymer materials are already overcome these shortcomings, this will make the car application field and scope of high polymer material to get a bigger development