Binder/tackifier materials are commonly used in preforming processes to preserve the structural integrity of the preform during processing. In the following resin infusion or injection process, this additional material will influence the resin flow. While the influence on fabric permeability is thoroughly examined in scientific literature, only few studies investigate the capillary behavior. By thermal activation of the binder, the material melts and spreads across the layer’s surface or is imbibed by the rovings.

In this study, capillary rise experiments in planar direction with four different carbon fiber fabrics were performed. The tested stacks were activated at different temperature levels and compressed in a vacuum bag, one of them with additional external pressure in an autoclave. In case of no external pressure, the processing and testing conditions showed a larger influence than binder activation temperature, while autoclave-conditioned specimens showed a decreased capillary rise velocity for all levels of activation temperature. Digital microscopy images of the specimens show that molten binder can create a thin film between the layers, which prevents peripheral flow and thus forces the fluid to rise in the (angulated) capillary tubes inside the rovings.

粘合剂/增粘剂材料通常用于预成型工艺，以在加工过程中保持预成型件的结构完整性。在接下来的树脂灌注或注射过程中，这种附加材料将影响树脂流动。虽然科学文献对织物渗透性的影响进行了彻底的研究，但只有很少的研究调查毛细管行为。通过粘合剂的热活化，材料熔化并铺展在层的表面上或被粗纱吸收。

在这项研究中，用四种不同的碳纤维织物进行了平面方向的毛细管上升实验。测试的堆叠在不同的温度水平下被激活，并在真空袋中压缩，其中之一在高压釜中受到额外的外部压力。在没有外部压力的情况下，加工和测试条件显示出比粘合剂活化温度更大的影响，而高压釜处理的样品显示出在所有活化温度水平下毛细管上升速度降低。样本的数字显微图像显示，熔融的粘合剂可以在各层之间形成薄膜，从而阻止外围流动，从而迫使流体在粗纱内的（有角度的）毛细管中上升。