Shanghai Daoqin Plastics Co., Ltd.

separation 1.1 equipment 1000l不锈钢 reaction 釜(油浴 electrical add hot,自 made 锚式搅拌 device,87rpm), 50l油 water separation device, tube/pipe cold device, true 空泵. 1.2 raw materials adipic acid, 1,4- butanediol, 甲苯均 is Domestic industrial product, water combined chlorine 化亚锡 is chemical pure agent,A试 agent made. 1.3 process process 438kg adipic acid, 306～310kg1,4- butanediol and amount (<0.1%)A试 agent add to reaction in, micro low 通N2, control material material temperature degree low 于140℃ reaction 5h,此时出 water amount already ultra- 理论 amount 55%. will hot temperature degree fast rise 至200℃,并 in rear maintain 不变. material material temperature degree 达180～190℃以 rear, add 入25kg甲苯回流 separation water. 2h rear 取样测 acid value, acid value low 于14mgKOH/g rear, add 入65g water combined chlorine 化亚锡,4h rear acid value drop 至4mgKOH/g below/following, decrease pressure,于0.01～0.02MPa pressure lower reaction 0.5～1h. cooling,出 material, 621kg white wax product,收 rate 83.2%(理论 value:85.5%), acid value <1mgKOH/g,羟 value 45～60mgKOH/g. 1.4 acid value testing methods 取1～2g polyester, solvent 于20ml1∶1苯-乙 alcohol solvent liquid in,以0.1NKOH standards solvent liquid 滴至酚酞指示 agent micro color. 2结果 and 讨论2.1 low temperature reaction and high temperature reaction due to ester reaction balanced 常数K value is 4～10, high temperature for reaction 顺利进行 is separation necessary. data table/sheet 明, same reaction time, in ensure water 55% front lower, low temperature stage/phase reaction temperature degree low,则 rear high temperature reaction time short; same reaction temperature degree, low temperature reaction time long is good. this main/primary is due to 1,4- butanediol in 140℃ above in obvious ring ether phenomenon,生 formed hydrogen 呋喃(THF)沸点远 low water 沸点, if low temperature stage/phase can utilizing reaction speed degree fast, reaction less has conditions, make material material separation, uniform low poly,则游离 butanediol amount more, high temperature stage/phase ether and 蒸发 导致 butanediol loss 失也就越 more,结果 not only polyester more alcohol molecular weight high, distribution scope/range wide effect/influence its use 效果, more important is reaction rear acid value difficult drop,不 不 large degree increase high temperature stage/phase reaction time. this reduce production efficiency,也 can can 因脱羧, understanding, oxidation and other reaction reinforcement yellowing,严 heavy has can can product waste. 2.2常 pressure reaction and true reaction in polymerization reaction in, especially is reaction rear 期, system viscosity very large,借助 decrease pressure small separation 子副产 material and amount raw materials is necessary. in 200℃时, pressure in 0.01～0.02MPa, acid value in 4mgKOH/g,仅需0.5～1.5h抽空 time. temperature degree rise high, true degree improve/increase or decrease pressure time long,初始 acid value can high. due to equipment in 密封方面 comparison difficult, true degree difficult 以随意 improve/increase,而 rise high temperature degree or long reaction time also very easy yellowing,故初始 acid value 不宜太 high. generally acid value in low 于4.0以 rear normal temperature lower very difficult again drop,即 make drop to 2.0 below/following also decrease pressure 抽空0.5h above. and 文献 6～8h, 0.01MPa, 220～240℃抽空 process conditions versus ratio,该 process advantages 不言而喻. 2.3 acid alcohol ratio for process effect/influence generally acid alcohol ratio is 1∶1.10～1.13, due to currently market upper Raw Materials in pure degree 方面 实际情况,兼顾 for value requirements,采取 acid alcohol ratio is 1∶1.13～1.15 is necessary. alcohol ratio/proportion improve/increase and process has 一定 关系, relatively high alcohol ratio/proportion can large shrink short rear reaction time, especially is in front reaction temperature degree low, reaction time relatively long especially 如此. amount alcohol can in 抽空时 recycling, in scope/range inner 并不会 for product value generate very large effect/influence. 2.4 catalytic and belt/tape water agent material material viscosity increase, reaction rear water 逐渐困 difficult, reaction speed degree obvious decrease slow. need fast make acid value drop to catalytic agent water combined chlorine 化亚锡 can has 效发挥 function 15mgKOH/g below/following,我们 in rear add a small amount of micro low belt/tape water,效果 very good. 3结论 above can 见, polyester more alcohol combined formed,无 must in high 于220℃ above high temperature lower 进行,也无 must long time in relatively high true lower 进行. need increase 一 足够 low temperature stage/phase add belt/tape water agent,即 can high combined formed high quality, combined solvent liquid method combined formed polyurethane ester use use polyester. 返回首页