This article mainly chooses MMA, BA, AA as monomers, and discusses the factors of graft polymerization with them, such as the addition sequence, addition amount and reaction temperature of the initiator and each monomer, and finds out the best graft polymerization process conditions. The rubber is first masticated, then stirred and dissolved with a mixed solvent at 70~80°C, and then the initiator BPO is added in batches. The first monomer MMA dissolved with BOP is added at 80~90°C for 20 minutes, and then added with the second monomer of BPO, after another 20 minutes, add the third monomer at 84~88 ℃ and stir for 45 minutes, keep warm for 1.5~2 hours, then get CR/MMA-BA-AA three-way graft polymerization adhesive, Peel strength is greater than CR/MMA-BA, its value is 6.6 KN.m-1.
Key words: Neoprene adhesive, Shoe glue, Multi-component grafted neoprene adhesive.
Cellulose ether MC and HPMC have good dispersion performance, emulsification, thickening, adhesion, film formation, water retention, and also have excellent water solubility, surface activity, stability, and dissolution in organic solvents.
The main products currently developed are RT series MC and HPMC varieties, whose grades are 50RT (Methylcellulose), 60RT (Hydroxypropylmethylcellulose), 65RT (Hydroxypropylmethylcellulose), 75RT (Hydroxypropylmethylcellulose), corresponding to the grades of DOW Chemical Company are Methocel A, E, F and K, respectively.
RT series products are very useful additives in building materials because of their cohesiveness, suspension stability and water retention. For example, they can be formulated into high-quality “ceramic wall and floor tile adhesives”, commonly known as rubber powder, which have been used in Beijing West Railway Station, the effect is good. In addition, it can be used as a gelled electrolyte in electrolytic capacitors and bonded electrode grids in electrical appliances, as atropine, aminopyrine and anal crystals in pharmaceuticals, and as a thickener for water emulsions in paints. In latex paint and water-soluble paint, it can be used as film-forming agent, thickener, emulsifier and stabilizer, etc. for wallpaper adhesion, water rewetting rubber powder, etc.
Key words: Methyl Cellulose, Hydroxy Propyl Cellulose, adhesive, application.
Development of water-based paper plastic hand glue
In recent years, a new process of pasting plastic film on printed matter has been developed. It is BOPP (biaxially oriented polypropylene film) coated with adhesive and then bonded together with printed matter after being pressed by a rubber cylinder and a heating roller to form a paper. / Plastic 3-in-1 print. This involves the problem of paper and plastic bonding. BOPP is a non-polar material, therefore, there is a need for an adhesive that has good adhesion to both polar and non-polar substances.
Mixing SBS adhesive with epoxy resin has good compatibility. SBS is an elastomer viscose. It can be seen from its failure curve that in order to optimize the adhesive destructive force of the viscose, it should be controlled around SBS: epoxy resin = 2:1. From the peel strength curve, it can be seen that when the ratio is high, the peel strength will be great, but the adhesion will also increase. In order to avoid adhesion, SBS: epoxy resin = 1:1~2.5:1 can be controlled to obtain a gently rising peel strength. Considering comprehensively, determine the SBS in the main glue: epoxy resin = 1:1~3.5:1.
The main function of using tackifying resin is to increase the bonding strength of the matrix and improve the wettability of the glue and the bonding surface. The tackifying resin used in this study is a rosin tackifier composed of ordinary rosin and dimerized rosin in different proportions. Through many tests, it is concluded that the percentage of dimerized rosin in the tackifier is 22.5%, and the peeling strength of the glue prepared according to this ratio is 1.59N/25mm (paper-plastic).
The amount of tackifier has a certain influence on the adhesive properties. The best effect is when the ratio of main glue and tackifier is 1:1. Peel strength N/mm plastic-plastic 1.4, paper-plastic 1.6.
In this study, MMA was used as the diluent to blend SBS and MMA. Experiments have found that the use of MMA can not only achieve the purpose of kneading the components in the colloid, but also reduce the viscosity and improve the adhesive force. Therefore, MMA is a suitable modified diluent. After experiments, the amount of MMA used is the total amount of glue 5% ~ 10% is appropriate.
Since the formulated viscose should be water-soluble, we choose white latex (polyvinyl acetate emulsion) as the water-soluble carrier. The amount of white latex accounts for 60% of the total viscose. After the water-based viscose is emulsified into a water-emulsion state through the dispersion and emulsification of the emulsified carrier, if its diluted consistency is not suitable for use, it can be diluted with water. This dilution method is both low-cost and non-toxic (no need to use organic solvents), and the best range of dilution water is 10%~20%.
In order to remove the residue of viscose, it is tested that dilute Na2CO3 solution is used as an alkalizing agent, and the effect is the best. The theory of the effect of the alkalizing agent may be that saponification reaction introduces some strong polar ions, such as sodium ions, so that the original insoluble rosin acid is converted into Soluble sodium salt. In addition, if too much strong base is added to the glue, the adhesive force will be lost, so that the glue fails, so the glue is not suitable for alkaline environment.
Appropriate process flow.
Post time: Apr-25-2024