RPVC异型材的木纹成型

Formalization of Wood Grain of RPVC Shaped Profile

介绍一种利用不同聚合度的ＰＶＣ树脂在相同温度下塑化程度的不同，从而导致流动性差异而产生木纹效果的方法，研究了原料配方、挤出工艺条件、口模结构和挤出生产线类型对木纹效果的影响。结果表明，采用平均聚合度与基料树脂聚合度相近的着色剂载体、选择与几种树脂平均分子量的塑化温度相当的挤出温度、采用压缩比和长径比较大（Ｌ／Ｄ２５）、塑化能力强但不带混炼头的单螺杆挤出机，能产生较好的木纹效果；不同的口模结构对基料和着色料的阻流不同，使木纹形状有所不同。经多次试验证明，本文所述产生木纹的方法切实可行，与二次印刷等后加工相比，具有更好的经济性。

The formalization of wood grain resulting from the difference of flowability of PVC with different polymerization degree and plasticization at same temperature is described,and the effects of formalizing,extrusion technology,mouthpiece structure and type of extruding line on the formalization were studied.The results showed when the colouring agent with average polymerization degree close to that of base resin was used,the extrusion temperature was about the same as the plasticizing temperature of the resin,the L/D ratio was high (25) and single screw extruder with powerful plasticization but without mixer head was used,fine wood grain could be formalized.Different mouthpiece structure had different damping force to base resin and colouring agent,resulting in different pattern of wood grain.The formalization technlogy given in this paper was proved by practice to be feasible,and was economical compared with some after processing like second printing.