Reasons for failure of wood adhesive preservatives

Many preservatives can inhibit the growth of bacteria in a short time, but this effect can not last long. This has plagued the storage, transportation and application of biomass-based wood adhesives. The main reasons may include the stability of the preservative itself and the formation mechanism of microbial resistance.

1.The stability problem of the preservative itself Bio-based wood adhesives are generally neutral substances, so the selected preservative itself must be stable under strong acid and alkali conditions to keep the drug in the storage time of the adhesive. Effective concentration. For example, sodium pentachlorophenol which is conventionally used is easily decomposed when light is heated, and chlorothalonil is decomposed in strong alkaline to release HCl. These characteristics are also a reference for the selection of preservatives. The BIT series of industrial sterilization products successfully developed in the 1970s include BIT raw powder, PT liquid, BTC liquid, BTG liquid, BTX liquid, etc. The main active ingredient is 1,2-benzisothiazolin-3-one. It is soluble and effective in the range of pH 4~12, and stable in the presence of ammonia. It has significant effects on bacteria, mold and yeast, and has high sterilization efficiency. It can be added by 0.005%~0.05%. The performance is stable, and the sterilization effect remains unchanged at 2000C. Easy to use, no pollution, no corrosion to metals. Low toxicity, LD50>1400mg?kg-1. Therefore, it can be used not only in the storage of soybean gum, but also in the anti-corrosion of the plate even after hot pressing (100~1400C); the antibacterial agent must have the anti-metabolism ability of anti-microbial hydrolysis to prolong the effective The antibacterial action time, such as bromocinnamaldehyde is not a natural organic substance synthesized by enzymatic synthesis, and is not easily enzymatically decomposed in the microorganism, and the antibacterial effective period can be increased by 350 times.

2. The mechanism of microbial resistance formation and its countermeasures Micro-mutation of microbial genes can form new new pathways for drug resistance and physiological metabolism. The core of the emerging anti-corrosion technology is to try to interfere with the self-balancing regulation mechanism that microbes have evolved to survive against extreme environments. Due to the narrow range of antibacterial and deworming of a single preservative, it is easy to induce microbial resistance in a short time. In order to minimize the negative effects of preservatives, the use of preservatives has become a worldwide trend and has achieved good results. Generally, two or more preservatives with additive effects or synergistic effects are mixed reasonably in a certain proportion, which not only overcomes the shortcomings of the use of a single preservative, but also produces some new characteristics. For example, the combination of antibacterial agents with different bacteriostatic mechanisms produces an ultra-wide antibacterial spectrum that cannot be achieved by a single agent, so that most of the mutants lose their basis for survival. Thereby interfering with the formation of microbial resistance and receiving the best antiseptic effect.