CN110358051A - 一种新型高弹性聚氨酯海港防撞缓冲块 - Google Patents
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Abstract
本发明涉及一种新型高弹性聚氨酯海港防撞缓冲块的制备工艺。该方法具体有以下步骤:步骤A:干燥聚醚多元醇;步骤B:制备聚氨酯预聚体;步骤C:合成聚氨酯;步骤D:聚氨酯形状剪切。该聚氨酯缓冲块具有以下优点:缓冲块的硬度适中、弹性好、形状可控、抗老化,是一种理想的防撞缓冲块。
Description
技术领域
本发明涉及聚氨酯领域,具体涉及一种新型高弹性聚氨酯海港防撞缓冲块的制备工艺。
背景技术
海港经常会停靠轮船,而轮船的制动性能不像汽车等路面交通工具,不能做到随时停止、精确控制,由于水的流动性,导致轮船很容易和港岸相碰撞,导致轮船表面的油漆损坏掉落,严重的甚至会造成船体破坏,对轮船的使用寿命会造成不良的影响。
海港的港岸边会经常设置一些缓冲物品,如废旧轮胎等,减少港岸对船体的破坏。但是废旧轮胎不够美观,而且废旧轮胎的大小不能根据船只大小和港口的实际情况定制,因此对轮船的保护不够到位。
本发明致力于开发一种新型高弹性的聚氨酯缓冲块,该缓冲块的硬度适中、弹性好、形状可控、抗老化,是一种理想的防撞缓冲块。
发明内容
本发明提供了一种新型高弹性聚氨酯海港防撞缓冲块:防撞缓冲块为长方体形状,长度为0.6-0.7m,高度为0.5-0.6m,宽度为0.3-0.4m,防撞缓冲块的侧面有横穿缓冲块的两个通道,通道的截面为圆形,直径为5-10cm,绳索穿过通道,缓冲块等距离固定于绳索上。
所述新型高弹性聚氨酯海港防撞缓冲块的配料质量份数为:改性MDI 45-55份、聚醚多元醇45-55份、混合多元醇70-80份、MOCA 20-26份、有机铋催化剂0.5-2份、有机锌催化剂1-3份。
所述的一种新型高弹性聚氨酯海港防撞缓冲块的制备工艺,包括以下步骤:
A.将聚醚多元醇、混合聚醚多元醇分别放入旋转蒸发仪中,在温度为100-105℃的条件下旋蒸干燥2-3h,然后冷却至室温备用。
B.将干燥后的聚醚多元醇倒入到反应附中,再向反应釜中加入改性MDI,将聚醚多元醇和改性MDI混合均匀,然后在70-75℃的温度下反应2-3h,并每隔15-20min取样一次,用滴定法计算异氰酸根含量,跟踪反应进度,当异氰酸根含量为8-15%时停止反应,得到聚氨酯预聚体,用旋转蒸发仪将预聚体脱泡,脱泡温度为30-40℃,脱泡聚氨酯预聚体密封保存备用。
C.将干燥后的混合聚醚多元醇、MOCA、有机铋催化剂和有机锌催化剂混合均匀,得混合料。
D.将步骤B中的脱泡聚氨酯预聚体和步骤C中的混合料加热到40-50℃,然后混合均匀,浇注到模具中,冷却至室温得到高弹性聚氨酯。
E.将步骤D中的高弹性聚氨酯进行形状剪切,并钻孔,得到所需形状的成品防撞缓冲块。
按照以上方法,可以制备出硬度适中且可调节的聚氨酯材料,该聚氨酯的邵A硬度在78-92之间,硬度可以通过控制异氰酸根含量和配方的质量份数来调节,在一定的范围内,随着异氰酸根含量的增大,邵A硬度呈增大趋势。
按照以上方法,可以制备出拉断伸长率不同的聚氨酯材料,该材料的拉断伸长率一般在356%-401%,因此该材料的弹性性能很好,并且弹性可调节,在一定范围内,随着异氰酸根含量的减小,该材料的弹性呈增大趋势。
按照以上方法,制备出的聚氨酯材料的抗老化性能佳,当老化温度为110℃、老化时间为20h,该材料老化后依然拥有很好的力学性能。拉伸强度、拉断伸长率、撕裂强度、邵A硬度均有较好的保持率。
按照以上方法,可以制备出形状可控的聚氨酯材料,在浇注的环节中,模具的形状可以根据需要改变,出模后的聚氨酯材料也可通过刀具的切割作用进行形状修整。
有益效果
1.该材料的邵A硬度在78-92之间,可通过制备工程的工艺参数进行调节,因此,不同港口可以根据船体的大小和港口的实际情况,制作不同硬度的聚氨酯缓冲块,以达到保护船体的作用。
2.该材料的拉伸性能好,有很好的弹性,因此船体在靠岸时,缓冲块能够对船体有很好的缓冲作用,延长碰撞作用力的时间,减小作用力对船体的压强,对船体有很好的保护作用。
3.该方法制备的缓冲块的大小和厚度可调节,一方面可以更换模具达到控制缓冲块的形状和大小,另一方面出模后的缓冲块也可以用刀具进行切割,制备出形状理想的缓冲块。
4.该材料的抗老化性能佳,可以使用很长时间,避免了经常更换缓冲块,降低了维护费用和使用成本。
附图说明
图1是本发明的制备流程图;
图2是本发明的示意图。
具体实施方式
下面对本发明较优的实施例做进一步的详细说明。
按照上述方法制备聚氨酯缓冲块,设定三个不同的异氰酸根含量,通过控制异氰酸根含量这个工艺参数对制备的过程进行调节,从而获得理想力学性能的聚氨酯缓冲块材料。
实施例1
一种新型高弹性聚氨酯海港及军用港口防撞缓冲块的制备工艺,见图1工艺流程图,按照如下步骤进行:
称取50份的聚醚多元醇和75份的混合聚醚多元醇放入旋转蒸发仪中,在温度为105℃的条件下旋蒸2.5h,然后冷却至室温备用。
将干燥后的聚醚多元醇倒入到反应附中,再向反应釜中加入50份的改性MDI,将聚醚多元醇和改性MDI混合均匀,然后在70℃的温度下反应2-3h,并每隔15min取样一次,用滴定法计算异氰酸根含量,跟踪反应进度,当异氰酸根含量为11%时停止反应,得到聚氨酯预聚体,用旋转蒸发仪将预聚体脱泡,脱泡温度为35℃,脱泡聚氨酯预聚体密封保存备用。
将干燥后的混合聚醚多元醇、22份的MOCA、1份的有机铋催化剂和2份的有机锌催化剂混合均匀,得混合料。
将脱泡聚氨酯预聚体和混合料加热到45℃,然后混合均匀,浇注到模具中,冷却至室温得到高弹性聚氨酯。
将高弹性聚氨酯进行形状剪切,并钻孔,得到所需形状的成品防撞缓冲块。
实施例2
控制反应时间,当异氰酸根含量为8%时停止反应,其他制备过程同实施例1。
实施例3
控制反应时间,当异氰酸根含量为15%时停止反应,其他制备过程同实施例1。
将以上三个实施例所制备的聚氨酯缓冲块进行力学性能测试,主要测试聚氨酯弹性体的硬度、拉伸强度、拉断伸长率和撕裂强度。测得数据见表1。
表1
观察表1,可得结论如下:异氰酸根含量对拉伸强度、拉断伸长率、撕裂强度和邵A硬度均有影响。拉伸强度随着异氰酸根含量的增大而增大;拉断伸长率随着异氰酸根含量的增大而减小;撕裂强度随着异氰酸根含量的增大而增大;邵A硬度随着异氰酸根含量的增大而增大。
橡胶的邵A硬度在86,该聚氨酯的硬度在78-92之间,硬度和橡胶差别不大,因此该硬度非常适合作为港岸的缓冲块材料;该聚氨酯的拉断伸长率在356%-402%之间,因此该材料有很好的弹性,作为缓冲材料,对船体等有很好的缓冲性能,可以有效延长作用力的时间,减小碰撞物体之间的压强,对船体起到保护作用;标准橡胶的拉伸强度为9.5Mpa,该聚氨酯的拉申强度在5.69-13.13Mpa之间,拉伸强度适中;撕裂强度在29.31-93.89KN/m之间,撕裂强度较强。
因此,该聚氨酯的硬度、弹性、拉伸强度和撕裂强度均十分符合缓冲块的性能要求,特别是异氰酸根含量为11%时,该工艺参数下聚氨酯的拉伸强度、拉断伸长率、撕裂强度和邵尔硬度分别为:9.41Mpa、378.53%、63.64KN/m和87,因此该聚氨酯非常适用于缓冲材料。
用异氰酸根含量为11%的聚氨酯缓冲材料进行老化性能测试,老化气氛为热空气,老化温度为110℃,老化时间为20h,将老化前后数据进行对比,见表2。
表2
观察表2,可得结论如下:该聚氨酯的抗老化性能佳,在温度为110℃、时间为20h的老化条件下,力学性能下降不多。拉伸强度由9.41Mpa下降至8.03Mpa,只损失14.67%;拉断伸长率由378.53%下降至314%,只损失17.05%;撕裂强度由63.64KN/m下降至55.51KN/m,只损失12.77%;邵尔硬度由87下降至84,只损失3.45%。因此,该聚氨酯的抗老化性能佳。
综上,该聚氨酯缓冲块不仅有良好的力学性能,对船体起到很好的保护作用;还有很好的抗老化性能,能够长时间使用。
以上内容是结合具体的优选实施方式对本发明所作的进一步详细说明,不能认定本发明的具体实施只局限于这些例子。对于本发明所属技术领域的普通技术人员来说,在不脱离本发明构思的前提下,还可以做出若干比例或参数的调整,都应当视为属于本发明的保护范围。
Claims (3)
1.一种新型高弹性聚氨酯海港防撞缓冲块,其特征在于:防撞缓冲块为长方体形状,长度为0.6-0.7m,高度为0.5-0.6m,宽度为0.3-0.4m,防撞缓冲块的侧面有横穿缓冲块的两个通道,通道的截面为圆形,直径为5-10cm,绳索穿过通道,缓冲块等距离固定于绳索上。
2.如权利要求1所述的一种新型高弹性聚氨酯海港防撞缓冲块,其特征在于:所述新型高弹性聚氨酯海港防撞缓冲块的配料质量份数为:改性MDI 45-55份、聚醚多元醇45-55份、混合聚醚多元醇70-80份、MOCA 20-26份、有机铋催化剂0.5-2份、有机锌催化剂1-3份。
3.如权利要求1所述的一种新型高弹性聚氨酯海港防撞缓冲块的制备工艺,其特征在于:包括以下步骤:
A.将聚醚多元醇、混合聚醚多元醇分别放入旋转蒸发仪中,在温度为100-105℃的条件下旋蒸干燥2-3h,然后冷却至室温备用;
B.将干燥后的聚醚多元醇倒入到反应附中,再向反应釜中加入改性MDI,将聚醚多元醇和改性MDI混合均匀,然后在70-75℃的温度下反应2-3h,并每隔15-20min取样一次,用滴定法计算异氰酸根含量,跟踪反应进度,当异氰酸根含量为8-15%时停止反应,得到聚氨酯预聚体,用旋转蒸发仪将预聚体脱泡,脱泡温度为30-40℃,脱泡聚氨酯预聚体密封保存备用;
C.将干燥后的混合聚醚多元醇、MOCA、有机铋催化剂和有机锌催化剂混合均匀,得混合料;
D.将步骤B中的脱泡聚氨酯预聚体和步骤C中的混合料加热到40-50℃,然后混合均匀,浇注到模具中,冷却至室温得到高弹性聚氨酯;
E.将步骤D中的高弹性聚氨酯进行形状剪切,并钻孔,得到所需形状的成品防撞缓冲块。
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