Automatic polycondensation reaction for amino resins comprises removing a sample, mixing with a solvent, measuring the turbidity temperature and light transmittance and terminating at the required temperature

    公开(公告)号:DE19935830A1

    公开(公告)日:2001-02-01

    申请号:DE19935830

    申请日:1999-07-29

    Applicant: BASF AG

    Abstract: Automatic polycondensation reaction comprises removing a sample, mixing with a solvent, measuring the turbidity temperature and light transmittance and terminating at the required temperature, enabling the production of large amounts of constant specification. Automatic polycondensation reaction by discontinuous determination of the turbidity point of a solution of the product comprises: (i) removing a sample volume V1 from a reaction solution; (ii) mixing V1 with a volume V2 of a solvent in an optically transparent measuring cell at a turbidity temperature TE which is different to the mixing temperature TM of the measured solution; (iii) homogenizing, thereby altering the temperature and measuring the transmittance of a specific wavelength of light; (iv) determining the temperature at which a leap in the light transmittance is recorded, TEmeasured; (v) removing the measured solution and optionally rinsing; (vi) optionally repeating steps (i) to (v); and (vii) terminating the reaction when TEmeasured reaches the required temperature value TS. An Independent claim is included for the apparatus used comprising an optically transparent measuring cell(s) with a cooling device and mixing or homogenizing device, a device for receiving a sample volume of a reaction solution, devices for giving a set volume and temperature and measuring the temperature and light transmittance of the measuring cell and comprising a sender and a receiver, devices for processing this data, pipes and optionally devices for rinsing the measuring cell and the pipes.

    Amino resins, useful as binders for derived timber prods. - contain specified urea derivs. obtd. by reaction of urea with poly:amine(s)

    公开(公告)号:DE4127615A1

    公开(公告)日:1992-03-05

    申请号:DE4127615

    申请日:1991-08-21

    Applicant: BASF AG

    Abstract: Amino resins (II). contain at least 0.5 wt. % urea deriv. of formula A-NH-Z-N(A)n-H (IIIA) or A-NH-R5(NH-A)-NH-A (IIIB). In formulae R5 = trivalent residue of 3-12C alkane. A = -CONH2. Z = -R1-, -R1-N(A)-R2- or -R1-N(A)-R2-N(A)-R3-(N(A)-R4-(with R1-R4 = 1-6C alkylene or hydroxyalkylene or 5-6C cycloalkylene). n = 1-6. Pref. (I) contains 1.0-20 wt.% (IIIA) or (IIIB) and (I) are obtd. by reaction of (IIIA) or (IIIB) with formaldehyde. (I) are amino resins (esp. UF or MFresins) contg. or based on (IIIA/B), (IIIA/B) are prepd. by reaction of corresp. polyamines with urea (as described, e.g. in US3390137), and the urea derivs. obtd. can then be reacted with formaldehyde at pH 8-12 to give amino resins. USE/ADVANTAGE - (I) are useful as binders for derived timber prods. Incorporation of even small amts. of (IIIA/B) gives binder solns. with markedly improved stability and the finished prods. (e.g. chipboard, plywood) have improved properties, esp. mechanical strength and low formaldehyde emission. (11pp Dwg.No.O/O)

    19.
    发明专利
    未知

    公开(公告)号:DE3784825D1

    公开(公告)日:1993-04-22

    申请号:DE3784825

    申请日:1987-08-25

    Applicant: BASF AG

    Abstract: A process is claimed for the prodn. of urea-formaldehyde resins (I) with U:F ratio from 1:1.0 to 1:2.1 and a solids content of 58-75 wt.% (opt. contg. melamine, phenol, etc.), by concn. of a condensate soln. (II), followed opt. by reaction with urea. (II) contains 38-55 wt.% dry matter, and is conc. by thin-layer evapn. to 58-72 wt.%, with recycling of 10-60 wt.% of the prod. soln. to the thin layer evaporator. Evapn. is performed in falling-film evaporator(s) in series or in parallel, pref. in two or three stages with recycling at each stage; evaporator is operated with film thickness about 1.5 mm and dwell-time 1-10 mins., pref. with steam at 2-6 bar, and at 48-100 deg.C; recycled soln. is treated with 60-70 wt.% aq. urea soln. before re-entering the evaporator; evapn. is performed at 850-100 mbar; pref., (II) contains 40-50 wt.% dry matter, and is conc. to 60-68 wt.%.

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