Increasing the production of high-performance natural fibres that minimise their impact on the environment is a challenge that flax (Linum usitatissinum L.) cannot address alone. In flax traditional production territories, hemp (Cannabis sativa L.) can be a complementary source of high added value fibres if their yield of long line fibres can be maximised to levels equivalent to the one of flax. The objective of the present work was to establish process parameters maximising the long line fibre yield using flax dedicated scutching and hackling devices. A lab-scale scutching/hackling device was used to establish sets of process parameters which best improve the long fibre scutching yield and as a consequence minimise the production of tow fibres. Decreases in straw processing transfer and beating speeds during scutching were necessary so that to be less aggressive on the straw and fibres. Very high long fibre yields were obtained after scutching and hackling at the laboratory scale (18 % of the hemp straw mass). These very high results, combined to high straw yield production in the field indicate that hemp can be a very productive source of high-performance fibres as these ones showed tensile properties completely suitable for a textile use as well as for load bearing composite materials. If the potential of high production yields and high mechanical and morphological properties was demonstrated at the lab-scale, this one should be improved at the industrial scale. Suggestions to reach this goal are provided to prevent too high transformation of long fibres into tows and to keep the mechanical potential maximum. When using optimised parameters and a lab-scale scutching/hackling device, it was demonstrated that hemp has the potential for providing equivalent amounts of long fibres per hectare than flax with tensile properties about 20 % lower than the ones of flax.

增加高性能天然纤维的产量，最大限度地减少对环境的影响，这是亚麻 ( Linum usitatissinum L. ) 无法单独解决的挑战。在亚麻传统产区，大麻 ( Cannabis sativa L.) 可以成为高附加值纤维的补充来源，如果它们的长线纤维产量可以最大化到与亚麻相当的水平。目前工作的目的是建立工艺参数，使长线纤维产量最大化，使用亚麻专用的切割和梳理设备。实验室规模的剪开/粗剪设备用于建立一套工艺参数，这些参数可以最好地提高长纤维剪开的产量，从而最大限度地减少丝束纤维的产生。有必要降低秸秆加工转移和打草过程中的打浆速度，以减少对秸秆和纤维的侵蚀。以实验室规模（大麻秸秆质量的 18%）进行剪草和砍伐后，获得了非常高的长纤维产量。这些非常高的成绩，结合田间秸秆产量的高产表明，大麻可以成为高性能纤维的高产来源，因为这些纤维显示出完全适合纺织用途以及承载复合材料的拉伸性能。如果在实验室规模上证明了高产量和高机械和形态特性的潜力，则应该在工业规模上进行改进。提供了实现该目标的建议，以防止长纤维过度转化为丝束并保持最大机械潜力。当使用优化的参数和实验室规模的切割/劈开设备时，证明大麻有可能提供与亚麻相同数量的每公顷长纤维，其拉伸性能比亚麻低约 20%。