| In our country, the forest coverage rate is low and wood raw materials are in short supply, and we need to increase the utilization of secondary fiber because of increasing demand for paper. The advantages of waste secondary recovery can recycling resources, reduce environmental pollution, save the native fiber simplified technological process and reduce energy consumption. The way to use secondary fiber is through the process of waste paper deinking. However, deinking technology is the key to the research and development of deinking agent.At present, the deinking agent researches mainly focuses on the deinking agent compound with small molecular surfactants; however, with the emergence of different quality printing ink, the current deinking agent can't meet the demand of the market yet, so it is imperative to develop a new surfactant with the good dispersion, emulsification, thickening. Polymer surfactant has become a new type of deinking because of its strong penetration, emulsification, and washing power for ink. In this study, two kinds of alpha-olefin suffocate (AOS) copolymer surfactant were prepared, and corresponding reaction conditions and deinking performances were tested. The research contents and results were as follows:(1) Anionic copolymer surfactant AOS-AA was synthesized by aqueous solution polymerization of sodium a-olefin suffocates (AOS) and acrylic acid (AA). The synthesis process was optimized, and the combined deinking performance of copolymer surfactant AOS-AA with nonionic surfactants and was investigated. The structure of anionic copolymer and the surface chemical prosperities were studied. Deinking effect among the own deinking agents, the mixed deinking agents and commercial deinking agent was compared by Scanning electron microscopy (SEM).The results show that the best deinking effect can be obtained when the preparation conditions of the product was as follows:n(AOS):n(AA)=1:2, w(APS)=3.0%, reaction temperature=85 ?, reaction time=5 h and polymer PH=8-9. When the deinking agents of m(AOS-AA):m(AEO-9)=1:2 and with dosage 0.2%, the whiteness can be reached as 72.1%ISO and the residual ink concentration is only 41.4 mm2·m-2. GPC showed that the mean molecular weight Mn was 3513 and the polydispersit Mw/Mn was 1.11. The SEM result shows that fiber surface has little ink particles, and the fiber surface becomes smoother.(2) A series of AAA Polymeric surfactants were synthesized by aqueous solution polymerization of sodium a-olefin sulfonate (AOS), acrylic acid (AA) and allyl polyethylene glycol (APEG-700). The synthesis process was optimized, and the combined deinking performance of AAA polymeric surfactant with nonionic surfactants was investigated. The structure of anionic copolymer and the surface chemical properities were studied. Deinking effect among the own deinking agents, the mixed deinking agents and commercial deinking agent were compared by SEM.The results show that the best deinking effect can be obtained when the preparation conditions of the product was as follows: n(AOS):n(AA):n(APEG-700)=1:3:1, w(APS)=2.5%, reaction temperature=80?, reaction time=5 h and polymer pH=8. When the deinking agents of m(AAA-700):m(AEO-9):m(AES)=1:2:1and with dosage 0.2%, the whiteness can be reached as 72.4% ISO and the residual ink concentration is only 51.2 mm2·m-2. GPC showed that the mean molecular weight Mn was 6216 and the polydispersity Mw/Mn was 1.56 The SEM result showed that fiber surface was smoother and the effective residual ink concentration was lower.(3) Respectively putting AOS-AA anionic copolymer surfactant and AAA-700 Polymeric surfactants to the orthogonal experiment and developing suitable synthesis conditions for flotation deinking.Through the orthogonal experiment, the best deinking effect can be obtained when the preparation conditions of the product were as follows n(AOS):n(AA)=1:2, w(APS)=3.0%, reaction temperature=85 ?, reaction time=5h;n(AOS):n(AA):n(APEG-700)=1:3:1, w(APS)=2.5%, reaction temperature=80 ?, and reaction time=5h. |
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