改性豆基蛋白胶粘剂的制备及应用

以改性异氰酸酯作为交联剂,制备改性豆基蛋白胶粘剂。探讨了交联剂、乳化剂和热压工艺条件等因素对该胶粘剂耐水胶接强度的影响。结果表明:当w(交联剂)=6%、u(乳化剂)=1.5%、热压时间为60 s/mm、热压压力为1.0 MPa和热压温度为120℃时,胶合板的耐水胶接强度为1.21 MPa,完全满足GB/T 9846.3—2004标准中Ⅱ类胶合板的使用要求,并且改性生豆基蛋白胶粘剂的适用期超过60 h。     

改性豆基胶粘剂在秸秆人造板中的应用

目前，农作物秸秆人造板所使用的胶粘剂大多为异氰酸酯型，虽其粘接性能优良，但有价格很责以及铺装板坯初粘性低等缺陷。近年来，国外对利用豆基胶粘剂制造环保型秸秆人造板的研究日渐增多。本文对此进行综合介绍，并根据我国国情展望了中国农作物秸秆人造板产品的发展前景。     

无醛膜状木材胶粘剂的制备与应用

采用熔融接枝法将MAH(顺丁烯二酸酐)接枝到LDPE(低密度聚乙烯)上,形成以PE(聚乙烯)大分子链为骨架、MAH为侧基的接枝共聚物(PE-g-MAH);然后采用挤出吹塑法制得无甲醛、无其他挥发性有毒物质的膜状胶粘剂(即无醛胶膜)。研究结果表明:当胶粘剂中w(MAH)=2%(相对于LDPE质量而言)、热压温度为130℃、热压压力为1.0 MPa、热压时间为6 min、冷压压力为1.3 MPa和冷压时间为3 min时,由无醛胶膜压制而成的II类胶合板的胶接强度(均超过1.30 MPa)符合GB/T 9846—2004《胶合板》标准要求。     

改性脲醛树脂胶粘剂的研究

主要利用混合改性剂，改进生产工艺以及施胶时加入填料等方法研究脲醛树脂胶粘剂的游离甲醛含量，剪切强度、耐水性等问题，得到低毒，综合性能良好的胶粘剂。     

桉树皮灰改性乐器胶粘剂制备及性能研究

为了提高乐器胶粘剂的耐湿热稳定性和粘接性能,采用桉树皮灰(A)和偶联桉树皮灰(CA)对涂料胶粘剂进行了改性处理,研究了其占胶粘剂占比,以及添加面粉后对酚醛胶粘剂的改性效果。结果表明,相同改性剂添加量时,CA改性胶粘剂的干胶合强度和湿胶合强度都高于A改性胶粘剂;在相同占比下,偶联桉树皮灰+面粉(CAF)改性胶粘剂的干胶合强度和湿胶合强度都高于桉树皮灰+面粉(AF)改性胶粘剂。A改性胶粘剂的固化起始点、峰值、终止点和热焓值的变化趋势与CA改性胶粘剂较为相似,CA改性胶粘剂的固化峰值温度低于A改性胶粘剂。CAF占比为25%时胶粘剂具有较好的干胶合强度和湿胶合强度。     

弱酸性起始条件合成改性UF胶粘剂的工艺及性能研究

以聚乙烯醇(PVA)和三聚氰胺(M)作为改性剂,采用正交试验法探讨了最终n[甲醛(F)]∶n[尿素(U)]、M掺量、M的加入方式和PVA掺量对脲醛树脂(UF)胶粘剂游离F含量和胶接强度的影响。研究结果表明:当最终n(F)∶n(U)=1.2∶1.0、在第2批U加入后添加M、w(M)=1%和w(PVA)=1%(均相对于U总质量而言)时,改性UF胶粘剂的游离F含量、胶接强度均满足GB/T 14732—2006标准要求;由上述UF胶粘剂压制而成的Ⅱ类胶合板,其F释放量(为2.89 mg/L)远小于GB/T 9846—2015标准中E2级指标要求。     

改性脲醛树脂胶粘剂合成的研究

研究了聚乙烯醇和三聚氰胺改性脲醛树脂胶粘剂的制备工艺和配方。以尿素和甲醛为单体,添加适量三聚氰胺和聚乙烯醇改性剂,甲醛和尿素最佳物质的量比为1.5∶1,尿素分3次投料,反应温度控制在85℃左右,反应时间60 min,可制得综合性能较好的低毒耐水脲醛树脂胶粘剂。产品固含量>60%,黏度(涂-4)120~150 s,剪切强度可达2.93 MPa,耐沸水时间可达122 min,游离甲醛质量分数可降至0.026%,产品质量完全达到国家规定的指标[1]。     

苯酚/聚乙烯醇改性脲醛树脂胶粘剂的制备及性能研究

以苯酚和聚乙烯醇(PVA)作为改性剂,采用正交试验法探讨了最终n(甲醛)∶n(尿素)、苯酚含量以及PVA含量对脲醛树脂(UF)的游离甲醛含量和胶接强度的影响。研究结果表明:当最终n(甲醛)∶n(尿素)=1.2∶1、w(苯酚)=20%和w(PVA)=1.0%(均相对于尿素总质量而言)时,苯酚/PVA改性UF的游离甲醛含量、胶接强度等均能满足GB/T 14732—2006标准中Ⅱ类胶合板的要求,并且相应胶合板的甲醛释放量(为1.70 mg/L)远低于GB/T 9846.3—2004标准中E2级指标要求。     

改性大豆蛋白基胶粘剂耐霉变性能研究

胶合板用大豆蛋白基胶粘剂具有原料来源广、可再生、价格低廉和无甲醛释放等优点,但其仍存在储存时间短、易霉变等缺点。采用单因素试验法探讨了防霉剂种类及含量对大豆蛋白基胶粘剂储存时间和胶合板耐霉变性能的影响。结果表明:当胶液中w(防霉剂C)=1.00%、胶液储存时间为1～14 d时,胶合板经28℃/相对湿度92%霉变处理42 d后,其胶接强度分别为0.85 MPa(比无霉变处理体系降低15%,此时胶液储存1 d)、0.88 MPa(比无霉变处理体系提高42%,此时胶液储存14 d)或变化不大(胶液储存4～10 d),说明含防霉剂C胶液的防霉耐久性相对最好。     

Bond quality of soy-based phenolic adhesives in southern pine plywood

Increased demand for wood adhesives, environmental concerns, and the uncertainty of continuing availability of petrochemicals have led to recent attention on protein-based adhesives. This study was conducted to investigate the glue bond qualities of soy-based phenolic adhesive resins for southern pine plywood. Two types of soy-based resins were formulated and tested. The first was made by cross-linking soy flour with phenol-formaldehyde (pf) resins at neutral pH. The second type was obtained by cross-linking soy flour hydrolyzates with pf resin under alkaline conditions. Plywood bonded with the neutral phenolic soy resins containing 70% soy flour and 30% 1.6 g/cm² pf without the use of extenders and fillers compared favorably with the traditional southern pine pf glue mixes. Plywood bonded with alkaline phenolic soy resins, containing 40 or 50% 0.5 g/cm² PF with the addition of extender (19% corn-cob powder), provided better adhesive glue bond properties than traditional southern pine pf glue mixes. These results suggest that soy-based phenolic adhesive resins have potential for the production of exterior southern pine plywood.     

葛根淀粉基胶黏剂制备与性能研究

研究开发以淀粉为主要原料的环保型胶黏剂替代"三醛类"木材胶黏剂,对彻底解决人造板及其制品的甲醛释放问题具有重要意义。以野生葛根淀粉为原料,通过降黏处理,并与聚醋酸乙烯酯和异氰酸酯复配,制备出胶合强度达到国家Ⅱ类要求的淀粉基木材胶黏剂。研究了降黏剂用量、降黏时间、聚醋酸乙烯酯和异氰酸酯用量对淀粉基木材胶黏剂胶合强度的影响。优化工艺条件下制备胶黏剂胶接胶合板的胶合强度为1.89 MPa,能够满足国家Ⅱ类胶合板强度要求。     

大豆基木材胶粘剂的研究进展

综述了大豆基木材胶粘剂的应用原理、历史和研究进展,重点介绍了豆胶的新型交联体系,指出了豆胶存在的问题.     

结构型紫外线固化胶粘剂的研究

介绍了结构型紫外线固化胶粘剂的特征及应用，重点研究了影响结构型紫外线固化胶粘剂粘接强度的因素。     

大豆蛋白胶粉胶合板热压工艺的研究

粉状胶粘剂具有贮存时间长、运输方便、含水量低的优点,为了防止热压过程中的＂鼓泡＂现象,促进大豆蛋白胶粉的应用,研究了用改性大豆蛋白胶粉制造胶合板的热压工艺,通过单因素实验和正交实验,得到最优组合为：胶粉施胶量120 g/m2,胶水施胶量230 g/m2,热压时间110 s/mm,热压压力132 MPa,此时胶合强度为0.98 MPa,达到国家标准Ⅱ类胶合板的要求。     

Peanut meal as plywood adhesives: preparation and characterization

Bio-based adhesives have attracted much attention due to its renewable and environment-friendly properties. This study describes a route for the preparation of a new bio-based adhesive from peanut meal. For this purpose, different types of raw materials (hot-pressed peanut meal and cold-pressed peanut meal) were compared. Moreover, the crushing methods and modification agents were investigated in great details. Furthermore, response surface methodology was applied to optimize the preparation conditions of peanut meal adhesive. The apparent viscosity and the Fourier transform infrared spectroscopy (FITR) of peanut meal adhesives were also evaluated to confirm the validity of the optimal preparation conditions. These results showed that hot-pressed peanut meal is a good candidate for adhesive materials and the addition of sodium dodecyl sulfate (SDS) improves the adhesive bonding strength. In addition, the regression model for the peanut meal adhesive preparation revealed statistical significance. Modification time and material liquid ratio had a significant effect on wet strength while the variables of modification temperature and the addition amount of modifier were insignificant. The optimal preparation conditions were determined as follows: modification temperature of 60?°C, modification time of 3?h, ratio of material to liquid of 1:3 and the addition amount of modifier of 3.2%. The average value of the adhesive bonding strength of 1.05?±?0.07?MPa was obtained, which is close to the predicted value. Under these conditions, the best wet strength and adhesive performance were achieved for the plywood.     

大豆蛋白胶粘剂的化学改性研究进展

由于石油危机和环境污染,传统的甲醛胶粘剂受到了严峻挑战,用天然可再生物质制取环保、绿色胶粘剂已成为趋势。文章就大豆蛋白胶粘剂性能、化学改性方法及其在环保型胶粘剂的应用前景进行全面描述。     

Glutaraldehyde-wheat gluten protein adhesives for wood bonding

ABSTRACT

Wheat gluten protein hydrolysate was used as a biomass feedstock to prepare environmentally friendly protein-based adhesives, with hydrolyzed wheat protein as control. Glutaraldehyde was used to modify it to obtain a glutaraldehyde-wheat protein (GP) adhesive. Polyethylenimine (PEI) was also used as a crosslinking agent. Plywood has been prepared and tested, and its performance was used to measure the wheat gluten protein hydrolysate adhesive bonding performance. Differential scanning calorimetry (DSC) and thermomechanical analysis (TMA) were used to analyze the adhesive thermal properties and the microstructures of the cured adhesives by scanning electron microscopy (SEM). The results show that modification by glutaraldehyde can effectively improve the bonding performance of wheat protein adhesives, the plywood bonded strength having been improved by its addition. The effect of PEI as a crosslinking agent became evident. It can greatly improve the bonding properties of glutaraldehyde-modified wheat protein adhesives. TMA analysis indicates that the glutaraldehyde-modified GP adhesive has a higher storage modulus than the unmodified one. The modulus of the adhesive increased after adding the PEI cross-linking agent.