马尾松化机浆DCS中潜在黏性物质稳定性的研究

Study on the Stability of Potentially Sticky Substances in DCS of Masson Pine CTMP

首先采用GC/MS技术对马尾松化机浆DCS中潜在黏性物质进行了表征,结果表明,黏性物质中的主要树脂组分为脱氢枞酸、亚油酸、油酸和棕榈酸等。接着,探讨了中性和酸性聚糖对树脂模型物(树脂酸R,脂肪酸O)稳定性的影响,结果表明,在没有钙离子存在的条件下,胶态的树脂可以通过静电机理自我稳定。乳液中一旦加入钙离子,胶态树脂颗粒就会迅速聚集,当钙离子与R、O的浓度比分别达到0.6∶1和1.6∶1时,胶态树脂颗粒会完全聚集。中性聚糖可以稳定胶态树脂颗粒,当加入的中性聚糖与R、O的浓度比分别超过0.2∶1和1.0∶1时,钙离子的加入不会引起颗粒的聚集。加入酸性聚糖会进一步恶化胶态树脂颗粒的稳定性;当体系中已存在的中性聚糖足以包裹胶态树脂颗粒时,酸性聚糖的负面效应会限定在一定范围内,体系保持一定的稳定性。

First, the characterization of potentially sticky substances in DCS of Masson pine CTMP was performed using GC -MS technique. Results showed that the major lipophilic substances were dehydroabietie acid, linoleic acid, oleie acid and palmitic acid. Then,the effect of neutral and acidic polysaeeharides on the stability behavior of typical wood resin models （resin acid R, fatty acid O） was investigated. Results showed that the colloidal resins could stabilize themselves by electrostatic mechanism if no calcium ions were added. Once the calcium ions were added, the colloidal resins would aggregate rapidly. When the concentration ratio of calcium ions to R and O reached 0.6 and 1.6, respectively, the resins would completely aggregate. However, no calcium -induced aggregation would occur, if the concentration ratio of added neutral polysaccharide to R and O exceeded 0.2 and 1.0, respectively. Acidic polysaccharide could further worsen the stability of the colloidal resins. When the neutral and acidic polysaccharides coexisted, the sterically stabilized resin acid R and fatty acid O would retain a certain level of stability, which indicated the limited adverse effect of acidic polysaceharide.