Patent GB-957611-A (GB)
Title: Organic polyborate resins
IPC: C08G8/28
Filed: 1960-09-20
Abstract: Pentaerythritol is reacted with borax, sodium tetra- or meta-borate or boric acid in an alkaline solution to form a borate, e.g. by shaking the boron compound in a 50% by volume mixture of petroleum ether and polyol; two layers separate, the complex being in the ether layer.  Glycerol and one of the above boron compounds in powder form may be mixed to give a boron-glycerol complex. Complexes of aromatic polyols e.g. isooctyl-chlorosatigenin, catechol, or 2, 3- or 1, 8-naphthalene diol may be similarly prepared.  Methylated bisphenols are prepared e.g. by reacting one mole bisphenol A with one mole formaldehyde and 0.06 mole LiOH.H2O at 60 DEG C. and pH 8.5-9 (see Example IX) In the examples, mono- or di-methylolated bisphenols are prepared from: I- 1/2 mole bisphenol A, excess formaldehyde and 0.03 mole LiOH at 60 DEG C. (gives bissaligenin A); V 3 moles bisphenol A, 13.7 mole formaldehyde, 0.72 mole LiOH.H2O at 60 DEG C.; VI 3 mole bisphenol A, 0.36 mole LiOH.H2O, and 3 mole formaldehyde at 50 DEG C.; VII 2 mole bisphenol A in methyl alcohol, 0.48 mole LiOH.H2O, and 9.12 mole H2CO at 60 DEG C.; VIII as VII with no methanol and only 0.24 mole LiOH.H2O; X one mole bisphenol A, methanol, 0.06 mole LiOH.H2O, and 1.2 mole H2CO at 50 DEG C; XI 3 mole bisphenol A, 0.72 mole LiOH.H2O, and 4 mole H2CO. Boric acid or borates are added to form complexes with the products, which complexes are polymerized.ALSO:An infusible resin is formed by heating a borate, H3BO3, or mixture of B2O3 and water with a bis-aromatic compound normally prepared by methylolating a phenol or bis-phenol in which one of the aromatic rings contains at least one -CH2OH or OH substituent group, the other containing an -OH group and at least one other -CH2OH or OH group, the substituents on the second ring being attached to adjacent carbon atoms.  The initial products are apparently linear, and on further heating become denser through cross-linking.  Many bisphenols from which suitable methylolated compounds may be prepared are listed and condensed-ring dihydroxy compounds are also given.  When an alkali-metal borate is used, it is necessary also to add a mineral acid.  When the aromatic compound contains only three hydroxyl groups in all, the initial products are more cross-linked then when 4 hydroxy groups are available, apparently because in the former case co-ordination of the boron atoms is possible, whereas in the latter case the 4 OH groups take up the boron's normal 3 valencies and also form a co-ordinate bond. Other organic compounds may be added, to vary the polymer's properties, e.g. amino compounds e.g. melamine, urea, aniline, isocyanoguanidine, or methylol derivatives or low polymers thereof, and these are preferably added when the phenolic compound is being methylolated prior to reaction with the boron compound. Also, aliphatic diols or polyols e.g. glycerol, mannitol, pentaerythritol, and di- or tri-pentaerythritol may be added, possibly as a boron complex, e.g. bis-pentaerythritol borate or a complex of isoctyl-chloro-saligenin and alkali borate or boric acid (for preparation of complexes, see Division C2).  Inorganic fillers e.g. asbestos, glass, silica or porcelain may also be added. In a preferred procedure, 1 mole of bisphenol A is mono-methylolated and one equivalent of H3BO3 added to give a pH of 2, followed by 2 moles of H2CO to reduce cross-linking.  Two layers separate, and excess H2CO and water are distilled off. The resin is cured at 50 DEG C. for several days, then at 100 DEG C. (if insufficient water has been removed previously, foaming now occurs), then at 185 DEG C. and finally at 200-300 DEG C. Examples are given, illustrating the various modifications mentioned above as well as the basic process.