This work aimed to determine the contact angle of adhesives in eucalyptus and pine wood and the influence on bonding, besides evaluating the wood-adhesive interface of glued joints with different adhesives and weights. Wood samples of two different species (Eucalyptus spp. and Pinus spp.) and five types of adhesives (polyvinyl acetate - PVA; sodium silicate - SS; resorcinol-formaldehyde - RF; bio-content polyurethane based on castor oil - BP; and modified silicate - MS) were used. For the contact angle determination, approximately 35 μL of each adhesive was inserted on the surface of the wood and the drops were photographed at five intervals after contact with the substrate. For the glue line determination, wood sheets with dimensions of 40 cm long x 10 cm wide x 0.6 cm thick were glued using three weights. Then slides were made and the images were captured using the Axio-Vision software. For the evaluation of the wood-adhesive interface, a scanning electron microscope was used. The mean values of contact angles ranged from 28.2 to 87.9° for eucalyptus wood and from 26.0 to 86.9° for pine wood. The smallest contact angles were obtained with the BP adhesive and the largest with the PVA adhesive. For eucalyptus wood, the lowest thickness of the glue line was 25.9 μm (SS adhesive) and the largest was equal to 149 μm (MS adhesive). For pine wood, the smallest thickness was 3.0 μm (BP) and the largest was 128 μm (PVA). Regardless of the wood used, the contact angle of the adhesives decreased with increasing time. The viscosities of the adhesives influenced the contact angle and the wettability of the wood. BP, PVA, and RF adhesives penetrated the wood, filling cell cavities adjacent to the main glue line.

这项工作旨在确定桉木和松木中粘合剂的接触角及其对粘合的影响，此外还评估了不同粘合剂和重量的胶合接头的木材 - 粘合剂界面。两种不同物种（桉树属和松属）的木材样品spp.）和五种类型的粘合剂（聚醋酸乙烯酯 - PVA；硅酸钠 - SS；间苯二酚 - 甲醛 - RF；基于蓖麻油的生物含量聚氨酯 - BP；和改性硅酸盐 - MS）。为了确定接触角，将大约 35 μL 的每种粘合剂插入木材表面，并在与基材接触后以五个间隔拍摄液滴。为了确定胶水线，使用三个重物粘合尺寸为 40 cm 长 x 10 cm 宽 x 0.6 cm 厚的木板。然后制作幻灯片并使用 Axio-Vision 软件捕获图像。对于木材-粘合剂界面的评估，使用了扫描电子显微镜。桉木的接触角平均值为 28.2 至 87.9°，松木为 26.0 至 86.9°。BP 粘合剂的接触角最小，PVA 粘合剂的接触角最大。对于桉木，胶线的最低厚度为 25.9 μm（SS 粘合剂），最大厚度为 149 μm（MS 粘合剂）。对于松木，最小厚度为 3.0 μm (BP)，最大厚度为 128 μm (PVA)。无论使用何种木材，粘合剂的接触角都随着时间的增加而减小。粘合剂的粘度影响木材的接触角和润湿性。BP、PVA 和 RF 粘合剂渗透木材，填充主胶线附近的单元腔。最小厚度为 3.0 μm (BP)，最大厚度为 128 μm (PVA)。无论使用何种木材，粘合剂的接触角都随着时间的增加而减小。粘合剂的粘度影响木材的接触角和润湿性。BP、PVA 和 RF 粘合剂渗透木材，填充主胶线附近的单元腔。最小厚度为 3.0 μm (BP)，最大厚度为 128 μm (PVA)。无论使用何种木材，粘合剂的接触角都随着时间的增加而减小。粘合剂的粘度影响木材的接触角和润湿性。BP、PVA 和 RF 粘合剂渗透木材，填充主胶线附近的单元腔。