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    Production of alkali-condensed phenol-urea-formaldehyde resin used e.g. for lignocellulosic material
    86.
    发明专利
    Production of alkali-condensed phenol-urea-formaldehyde resin used e.g. for lignocellulosic material 未知

    公开(公告)号：DE19653627A1

    公开(公告)日：1998-06-25

    申请号：DE19653627

    申请日：1996-12-20

    Applicant: BASF AG

    Inventor： SCHATZ HERMANN ,  REINHARD STEPHAN DR ,  EBNER MANFRED ,  LEHMANN GUNTER ,  LEHNERT HEINZ ,  RACHWALSKY UWE DR ,  FATH WOLFGANG DR

    IPC: B27N1/02 ,  B29B7/14 ,  B32B21/00 ,  C08G14/08 ,  C08J5/04 ,  C08L61/34 ,  C08L97/02

    Abstract: A process for the production of an alkali-condensed phenol-urea-formaldehyde (PUF) resin with a mol ratio of P:F:U = 1:(1.5-3.5):(0.3-2.5), comprising: (a) preparation of a PF condensate by alkaline condensation of P and F up to a viscosity of 100-5000 mPa.s; (b) production of a PF resin by further condensation to a viscosity of more than 5000 mPa.s; and (c) reaction of the PF resin with urea. The novelty is that stage (b) is carried out in an extruder. Also claimed is a PUF resin obtained by this process. Preferably stage (b) is carried out in an extruder at 90-150 deg C, preferably in a continuous single- or twin-screw mixer, a twin-screw continuous kneader or a continuous multi-screw kneader. Stages (a)-(c) may be carried out continuously. The PF resin is produced in stages (a) and (b) by starting with 60-90% of the total amount of formaldehyde required, and then reacted in stage (c) with the remaining 10-40% F and the urea, possibly in the form of a UF precondensate. The PF resin obtained in stage (b) has a viscosity of more than 5000 to 100,000 mPa.s. The final PUF resin has a solid content of 40-70 wt% and a mol ratio of (phenol):(alkali hydroxide) = 1:(0.4-1.2), which may be reduced to 1:(0.9-1.5) before processing by adding more alkali hydroxide.

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