厚皮香栲胶鞣革性能的研究

本文研究了厚皮香栲胶的鞣革性能，结果表明，厚皮香栲胶在渗透性与结合性方面与黑荆树和杨梅栲胶接近，是国产的一种优良栲胶。适合于鞣制底革、装具革、凉席革以及结合鞣革，其成革坚实、饱满、色泽为红棕色。     

马占相思栲胶的性质及应用研究

对广西百色林化总厂试生产的马占相思栲胶的物理化学性质及应用特点进行了研究。结果表明,马占相思栲胶的性质与进口的荆树皮栲胶相似,收敛性中等,粘度低,鞣制过程中沉淀少,渗透速度快,成革颜色浅淡,可用于生产重革,也可用于轻革的复鞣。用其复鞣蓝湿皮,革的丰满性、柔软性和粒面细致度等各项性能均优于余柑杨梅栲胶,接近荆树皮栲胶,可以代替进口的荆树皮栲胶。     

荆树皮栲胶降解改性产物与铬结合鞣研究

研究了荆树皮栲胶降解改性产物与铬鞣剂的结合鞣性质。结果表明：（1）荆树皮栲胶降解改性产物-铬结合鞣,可缩短植鞣的时间,有明显的增厚效应,能提高二层和三层革利用率,在三氧化二铬用量为0.5%的条件下使皮革的收缩温度超过100℃,总增厚率大于47%。用5%荆树皮栲胶降解改性产物与1%铬鞣（以Cr2O3计）结合鞣皮革的收缩温度为109℃,总增厚率达47.2%。（2）结合鞣中植物鞣质分子量大小和分布与鞣性、增厚率有直接的关系。     

落叶松栲胶的接枝改性及其应用的研究

落叶松是我国东北、内蒙地区大森林主要树种,资源丰富,树皮含鞣质7～12%,属凝缩类。牙克石栲胶厂用作原料生产栲胶,全国各皮革厂都在用它来鞣革。在国内     

厚皮香栲胶通过省级鉴定

由成都科技大学皮革工程系,皮革研究所与云南思茅栲胶厂、云南省林业科学院、思茅地区经协办共同完成的研究成果《厚皮香栲胶物理化学性质及鞣革性能的研究》,于1988年11月12日在成都通过云南省级评议。经代表审议认为正式开发鞣料新品种—厚皮香的研究,国内尚属首次,国外未见报导;研究结果对厚皮香栲胶的生产、应用都有实际意义和指导作用。     

国产栲胶鞣制工业革试验研究

1977年轻工业部向我厂下达了“应用国产栲胶鞣制工业革的试验研究”项目后,我们对柚柑、杨梅等六种国产栲胶及进口荆树皮栲胶进行了各种性能分析;单一栲胶鞣革     

国产与进口栲胶性能对比试验

在关于使用国产栲胶鞣制特种工业革的科学实验中,我们进行了杨梅、柚柑、落叶松、橡碗等四种国产栲胶与进口荆树皮栲胶     

BA浅色栲胶在制革中的应用研究

BA浅色栲胶是广西百色林化总厂在国内首次研发的一种浅颜色的栲胶新产品。本文对这种栲胶在制革中的应用进行了试验研究。结果表明，BA浅色栲胶的鞣革性能优良，接近进口的荆树皮栲胶，在制革过程中可以代替进口的荆树皮栲胶。     

植-无铬鞣剂TWT结合鞣法研究

研究了无铬鞣剂TWT与植物鞣剂的结合鞣法。结果表明,TWT鞣剂与荆树皮栲胶和杨梅栲胶进行结合鞣制,成革收缩温度较高。较佳的鞣制条件为:首先用20%的荆树皮栲胶或杨梅栲胶进行鞣制,然后在pH4.0~6.0和50℃的条件下,用6%的TWT结合鞣3 h,成革的收缩温度可达到94℃。本研究进一步对植-改性戊二醛、植-噁唑烷和植-TWT三种结合鞣法进行了比较,结果表明植-TWT结合鞣制皮坯对加脂剂的吸收率最高,成革中游离甲醛含量最低。因此,植-TWT结合鞣法具有突出的环保性能。     

EH(醚化N-羟甲基丙烯酰胺)与栲胶结合鞣的研究

本文研究了经醚化改性的N-羟甲基丙烯酰胺(简称EH)与栲胶进行结合鞣革,首先研究了具有代表性的三类国产栲胶:水解类的橡碗栲胶、缩合类的木麻黄、落叶松栲胶和混合类的杨梅栲胶与EH结合鞣革对Ts的影响及鞣得成革样品耐水、酸、碱溶液洗涤性能,然后研究了杨梅栲胶与EH结合鞣制时,栲胶不同用量、介质pH对Ts的影响;最后,对EH与杨梅栲胶结合鞣革的水洗液进行了初步探讨。结果表明:先经栲胶鞣制然后用EH处理,可以提高样品革的湿热稳定性,使革的Ts达94℃,样品革耐水、酸、碱溶液洗涤性能好。其中杨梅栲胶与EH结合鞣制效果最明显。结合鞣革的初步研究表明:EH对革中的栲胶有固定作用。     

植物鞣质与胶原的反应机理研究

本研究是国家教委博士点基金资助项目。本文研究了水解类植物鞣质结构与疏水性的关系,并且通过研究鞣质拟物与氨基酸和明胶的反应,从分子水平阐明了水解类植物鞣质分子中的棓酰基与胶原氨基酸的脂肪侧链间的疏水反应,是鞣质与胶原的一种主要结合方式。     

植物鞣质作染料染毛皮的研究

应用不同的化学试剂处理厚皮香、橡碗、木麻黄、冷杉栲胶和五棓子浸提物以改性调色,并试染了纯毛绒线,获得了多种新型染色物质——鞣质染料。染色理论性的试验,所进行的吸附等温线试验,验证了染色吸附理论;几种鞣质改性后均作了光谱测验,说明改性调色后,产生了多种新的染色物质。选用有染色价值的厚皮香、橡碗栲胶染毛皮,染色效果均能达到染料质量标准的要求,可适用于毛皮染色。     

重度亚硫酸化改性栲胶鞣质分析方法

应用鞣质测定的标准方法对重度亚硫酸化改性栲胶进行分析 ,其鞣质含量仅为 3 .2 %,而鞣质的定性试验却表明滤液中仍存在大量的鞣质。说明需对此方法进行改进以适合此类产品的分析。在鞣质测定方法的基础上作了适当改进 ,对测定时的pH值、振荡时间及称样量对鞣质含量测定的影响进行研究 ,结果表明 :称样量为 10 10 .5 g/ 10 0 0ml、测定 pH值为 4.0± 0 .1、振荡时间为 10min时 ,鞣质吸收完全 ,并且平行实验的相对误差小 ,重现性好。这一改进方法可以作为重度亚硫酸化改性栲胶的生产控制和产品质量分析     

毛杨梅栲胶磺甲基化改性及其产物的应用研究

研究了毛杨梅栲胶的磺甲基化改性方法。测试表明，产物的水溶性、耐盐析和耐酸性以及在溶液中的稳定性均提高，但收敛性约有降低。鞣制试验表明，磺甲基化栲胶的渗透速度快，对革的填充性及成革丰满度均比未改性栲胶和亚硫酸盐处理栲胶优良，成革粒面平细．     

ANTIOXIDANT ACTIVITY OF CONDENSED TANNINS OF BEACH PEA, CANOLA HULLS, EVENING PRIMROSE, AND FABA BEAN

Condensed tannins were extracted from beach pea, Cyclone canola hulls, evening primrose and faba bean using 70% aqueous acetone. The dried crude tannin extracts were purified on a Sephadex LH-20 column using first 95% ethanol as a mobile phase for elution of nontannin phenolics and then 50% aqueous acetone to elute tannins. The total content of polyphenolics in tannin extracts ranged between 10 and 405 mg catechin equivalents per 1 g extract. All tannins extracts displayed a marked antioxidant activity in a β-carotene-linoleate model system. Evening primrose and faba bean tannin extracts exhibited the best     

The formulation and commercialization of glulam pine tannin adhesives in Chile

The results of fingerjointing and glulam industrial trials in Chile using a “honeymoon” fast-set adhesive system manufactured using commercially-produced mildly-sulphited pine tannin extract are reported. The results obtained satisfy the relevant international standards specifications and constitute the first occasion that a commercially produced pine tannin adhesive has been used succesfully in industrial productions runs. This pine tannin adhesive is now available commercially in Chile for fully-exterior, structural-grade, solid timber applications. A new “honeymoon” type adhesive formulation had to be developed due to the peculiar gelling of the pine tannin extract used. The Chilean pine tannin extracted from a mixture of Pinus insignis and Pinus radiata shows gel times longer than what reported for other conifer tannins with the exception of Pinus brutia. Such differences in curing rate are tentatively reported to be related to the relative branching of the different conifer tannins.     

Autocondensation-based,zero-emission,tannin adhesives for particleboard

Interior grade particleboard prepared with tannin adhesives to which no aldehyde hardener was added were prepared. The hardening of the tannin adhesive was induced by the reaction of autocondensation tannins undergo when catalyzed by a lignocellulosic substrate or by a weak Lewis acid as alkali dissolved silica. The more alkaline the tannin extract solution the higher the ceiling internal bond strength that the particleboard bonded with it can reach. Differences between four commercial tannins are discussed. Pecan nut tannin and pine tannin need only lignocellulosic induced autocondensation to give excellent interior grade particleboard. Slower reacting tannins such as mimosa need instead both the catalytic effect of the substrate as well as that of a weak Lewis acid such as silica. Only pecan nut tannin appears at this stage to be able to give boards of acceptable dry internal bond strength at industrially significant pressing times.     

Effect of tannins on the in vitro growth of Escherichia coli O157:H7 and in vivo growth of generic Escherichia coli excreted from steers

The effect of commercially available chestnut and mimosa tannins in vitro (experiment 1) or in vivo (experiment 2) on the growth or recovery of Escherichia coli O157:H7 or generic fecal E. coli was evaluated. In experiment 1, the mean growth rate of E. coli O157:H7, determined via the measurement of optical density at 600 nm during anaerobic culture in tryptic soy broth at 37 degrees C, was reduced (P < 0.05) with as little as 400 microg of either tannin extract per ml of culture fluid. The addition of 200, 400, 600, 800, and 1,200 microg of tannins per ml significantly (P < 0.01) reduced the specific bacterial growth rate when compared with the nontannin control. The specific growth rate decreased with increasing dose levels up to 800 microg of tannins per ml. Bacterial growth inhibition effects in chestnut tannins were less pronounced than in mimosa tannins. Chestnut tannin extract addition ranged from 0 to 1,200 microg/ml, and a linear effect (P < 0.05) was observed in cultures incubated for 6 h against the recovery of viable cells, determined via the plating of each strain onto MacConkey agar, of E. coli O157:H7 strains 933 and 86-24, but not against strain 6058. Similar tests with mimosa tannin extract showed a linear effect (P < 0.05) against the recovery of E. coli O157:H7 strain 933 only. The bactericidal effect observed in cultures incubated for 24 h with the tannin preparations was similar, although it was less than that observed from cultures incubated for 6 h. When chestnut tannins (15 g of tannins per day) were infused intraruminally to steers fed a Bermuda grass hay diet in experiment 2, fecal E. coli shedding was lower on days 3 (P < 0.03), 12 (P = 0.08), and 15 (P < 0.001) when compared with animals that were fed a similar diet without tannin supplementation. It was concluded that dietary levels and sources of tannins potentially reduce the shedding of E. coli from the gastrointestinal tract.     

不同单宁含量的杨梅栲胶鞣革的渗透速度

采用单宁含量分别为69．4％、67，4％、65．0%、63．5％、60．5％的杨梅栲胶进行鞣革对比试验．结果表明：渗透速度与栲胶的单宁含量不成正比关系。单宁含量63．0％ 以上的栲胶，渗透速度约为0．4mm／d，与单宁含量无关；而单宁含量为60．0％的栲胶，渗透速度明显减慢，约为0．2mm／d。由于实际生产的栲胶产品单宁含量几乎都在65．0％以上，小于63．0％的极少。因此认为，市场销售的栲胶均可单独适用于鞣制重革，不会影响鞣期。     

Fast vs. slow-reacting non-modified tannin extracts for exterior particleboard adhesives

Non-fortified, non-modified tannin extracts, rather than chemically-modified tannin adhesives intermediates, can be used as effectively to produce excellent exterior grade particleoboard at fast pressing times of industrial singnificance, with considerable advantages in both handling and cost. This can be achieved by simple pH-controlled reactivity adjustments of the tannin extract in the glue mix. This new concept is shown to be applicable to all types of polyflavanoid tannin extracts: Pine, mimosa, pecan, quebracho, and gambier tannin extracts are compared as regards their performance and capabilities. The new concept applied to the faster-reacting tannins, such as pine tannin and pecan tannin extracts, is shown to produce fast hot-pressing rates and excellent high moisture content tolerances which are undreamed of for the slower-reacting tannins, modified or non-modified, which are traditionally associated with thermosetting wood adhesives. Industrially used techniques to control well viscosity and pot-life of the glue-mixes of accelerated tannin adhesives are also presented.