2014年3月6日星期四

Select the general principles of PVC lubricants

As mentioned above, must be reasonable taking into account the liquidity, the rate of anti-sticking and plasticized PVC resin. That is certain to make the external lubrication balanced economy can achieve the purpose of continuous production . Research and practice show that : it is not 100% plasticized best quality products , the highest mechanical  WSD Stabilizers for pipe properties [ 8 , 9 ] . Moreover , for a number of reasons, the degree of plasticization of the different products have different requirements. Incomplete plasticizing , not only of good quality , high yield, low energy consumption, and can reduce the amount of heat stabilizers , help reduce costs and increase production. In full consideration of heat stabilizers and other additives for lubricants and other factors affecting the premise , through the adjustment of external lubricant variety and quantity can be regulated plasticizing rate, increased resin flow and improve adhesion. Selection Lubrication System General Experimental Procedure ( a ) standard sample
With a processing performance , high quality equipment in the same class of the same type of high-speed mixing material products , with a torque rheometer experiment . Test its plasticizing time , when plasticizing plasticizing peak torque and peak width and slope after slope . Then  WSD Chrolinated polyethylene the adjustment , external lubricant varieties and quantities to match the standard sample as close as possible . ( 2 ) First, to change the PVC melt flow through the variety and amount of lubricant that is changing the melt viscosity ( plasticized torque value ) ( 3 ) under basic adjust melt viscosity ( plasticized torque value ) of the premise, through changes in external lubricant varieties and quantity adjustments plasticizing time ( ie plasticizing rate ) . Of course, the number of external lubricant change or change their species, the peak is also affected by the plasticizer . ( 4 ) After the release of liquidity , plasticizing time ( rate ) basically satisfied with the melt, should examine the adequacy of anti- adhesion , anti-sticking , if still insufficient , may be appropriate to scale up the inner and outer lubricant consumption. If the release of already feeling ( non-stick rheometer rotor mixing head ) , indicating that there may be an excess amount of lubricant ( which is balanced by a high level of lubrication ) , may be appropriate to reduce the number of internal and external lubricant in an amount up to up slightly tacky . On the basis of the appropriate number of additional internal and external lubricant is that it is not sticky , it is balanced by a lower level of lubrication is closer to the equilibrium level of practical application of lubrication . Although a high level of lubrication average system can improve the thermal stability of PVC , reducing the amount of heat stabilizers reduce formulation costs , but external lubricant precipitation phenomenon may be more severe , continuous production adversely . Meanwhile , it is possible that the rate of increase in downtime , reduced productivity , increased scrap rates , increasing the production costs and the inconvenience of many operations and may  WSD Aluminum hydroxide affect the performance of secondary processing . ( 5 ) enlarge the recipe above experiments were initially identified in the production of amplification tests found any deficiencies , then targeted adjustment system , so repeated several times to design a more satisfactory balance lubrication system, to achieve economic , the purpose of continuous production of quality products . If there is no standard formula , you can ask for the heat stabilizer or lubricant manufacturer reference formulation , pilot production by reference to a formula , to identify problems , and then refer to the recipe to make Brabender rheological experiments , as described above with reference to the rheological test results program improvement, or use cheaper products for the original reference lubricant formulations be replaced. Effects of experimental data on the proportion of actual production volume of material due to the large amount of experimental material produced too poor, laboratory equipment too different from the actual production equipment , experiment materials and large-scale production of materials suffered heat and shear force experience the difference is too big and other reasons, from the experimental data obtained torque rheometer have slight differences are likely to have a serious impact on the large-scale production . Here are the results of the three formulations and circumstances in production for reference formula is # 1 with a parallel twin-screw factory in Shandong normal production tubing mixes measured data . 2 # recipe is a heat stabilizer foreign company recommended formula , allegedly in the United States has been widely used in conical twin screw extruder organotin heat stabilizers pipe, but in parallel twin -screw extruder , only in far lower than the normal speed in order to produce qualified pipe, host a speed slightly improved , that would be too large due to host torque automatic alarm , not the normal production . Analysis of the experimental data above : 1 # 2 # recipe formulation than the plasticizing time short 12s, ie 414 % of the time is short ; although plasticized formulations torque 2 # 1 # recipe only larger than 2%. However, in the actual production for the difference is very large . 3 # # recipe is the author of two formulations based on the improved formulation , plasticizing time 3 # 1 # extend over 20s, to extend the 7% ; plasticizing torque than 1 # 3 # Small 013N · m, smaller 018% . Results 3 # recipe can normally use parallel twin -screw extruder qualified pipe.

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