How to make a suitable blown film formula

    In order to obtain satisfactory film quality for blown film, in addition to have a suitable blown film machine, a suitable formula is also required.    

    The main effects that the blown film formula needs to achieve are: good tensile strength, good film stretch rate, good film tearing strength, and strong hand feeling. These are the four main functions that the blown film formula must achieve.    

    The key skills of the formula:

1. Understand the resin density

2. Understand the resin melt index

3. Understand the density of the comprehensive formula, so that you can know the performance of the formula.    

    The basic principle of ingredients: as far as possible to reduce costs while meeting customer needs. There are several main points to reduce costs, namely: 1. Add filler to increase weight, 2. Add recycled materials to replace new materials. But pay attention to the four prerequisites, otherwise the customer will run away, and the gain will not be worth the loss!    

    Shanghai Duxia Industry and Trade Co., Ltd. now introduces some common blown film formulas and explains them for free, hoping to help our downstream customers

    Note: Part of the formula does not represent all, it can be freely adjusted, and it needs to be matched according to the performance of the machine.

    Note:    

    1. The viscosity of the new ldpe material is quite high, so a certain amount of slip agent (opening agent) must be added    

    2. lldpe mainly increases the tensile force of the film, adding more lldpe will increase the haze of the film and reduce the opening. Of course, hdpe transparent first-level recycled materials can also replace lldpe to reduce costs, but the tensile force will be reduced.     

    3. Classification of ldpe recycled materials, there are transparent and colored ldpe recycled materials, which color is best used for plastic bags, so as to avoid cross-color affecting the effect of color masterbatch. It is best not to add colored recycled materials to make transparent bags. If you want to increase the transparency of low-pressure materials, it is best to add transparent high-pressure recycled materials. The disadvantage is: the film is soft, too much will reduce the feel, the advantage: the gloss is enhanced.    

    4. The main function of the filler is to increase the weight of the film, reduce the cost, and modify the function of the raw material. Can increase the stability of the blown film. High-pressure filling materials generally do not require too much addition because it is easy to cause the film to be brittle, torn with light tearing, and the tension is not good. Unless you make a very thick aquatic bag. Poor filling materials often cause the bag to be ironed poorly, water splashes, poor dispersion, influence on tensile strength, and poor tearing strength, etc. Special attention should be paid to it. (There are also fillers to increase the tensile force.) Barium sulfate and nano-filling have slightly better transparency than general fillings.    

    5. The main function of the metallocene is to resist puncture. If there is frequent air leakage during the film blowing process, it can be added. Of course, the film with special requirements must also be added to cause bubble breakage and air leakage to the crystal points. Can enhance the weldability of raw materials.   

     6. The slip agent, also known as the opening agent, is mainly to reduce the viscosity to prevent the film from sticking together and not easy to open. It is especially necessary to add when the thickness of the high-pressure film is very thin, but it should not be added too much. Too much will cause winding and slippage.    

    7. The color masterbatch mainly depends on the coloring power of the purchased color masterbatch. If the coloring is good, you can actually add less color masterbatch. If the coloring power is poor, you must add more color masterbatch. Color masterbatches are basically divided into three types: new color masterbatches, recycled color masterbatches, and ordinary color masterbatches.    

    Shanghai Duxia Industry and Trade Co., Ltd. is an enterprise focusing on manufacturing plastic packaging machinery.The main products of Shanghai Duxia Industry and Trade Co., Ltd .: film blowing machine,stretch film blowing machine, printing machine, plastic bag making machine, plastic recycling machine.If you need any of the above machines, please leave your information. Our sales will contact you as soon as possible.