CN114506127A - 一种重晶石医用防护服材料及其制备方法 - Google Patents
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Abstract
本发明属于医用防护服材料技术领域,具体涉及一种重晶石医用防护服材料及其制备方法。本发明提供的重晶石医用防护服材料,由隔离层和外防护层构成,所述隔离层的厚度为190~300μm,所述外防护层的厚度为150~230μm;其制备方法包括以下步骤:物理提纯重晶石并磨粉;将所述重晶石细粉末与聚乙烯按照重量比:3.5:6.5或4:7.5,均匀揉和,热压成型,得到隔离层非织造布;将所述隔离层非织造布与丙纶纺粘无纺布进行热轧复合得到重晶石医用防护服材料。该材料兼具防辐射性能良好和制备成本低的优势,并且具有良好的透气及透湿性能,经洗涤和消毒后可以重复使用。
Description
本申请是申请日为2017年10月08日、申请号为201710926767.0、发明名称为《一种重晶石医用防护服材料及其制备方法》的分案申请。
技术领域
本发明属于医用防护服材料技术领域,具体涉及一种重晶石医用防护服材料及其制备方法。
背景技术
近年来,随着先进的X射线诊断,以及心血管造影术、血管成形术的发展和快速普及,放射介入治疗广泛开展。而在心血管造影术、血管成形术等精细手术中,医学放射学工作者须长时间曝露在X射线场中工作。若机体在较长时间内连续或间断受到X射线照射且达到一定剂量时,组织中的细胞被电离辐射灭活,从而引起以造血组织损伤为主的放射性损伤,甚至导致白血病,皮肤癌等。如果眼睛长期受到超剂量辐射时,会引起晶状体病变,发生放射性白内障。
关于医疗X射线防护的研究大多局限于墙体、建筑材料、医疗设备的挡板等,对于医护人员自身的防护装备关注较少,而且由于成本等方面的原因,大部分医疗单位无法使用防护性能较好的防护服,特殊情况下使用的也是一次性防护服,造成资源浪费,成本居高不下,致使广大医护人员的健康安全难以得到保证。早期的医用X射线防护服一般以铅为屏蔽材料,由于其重量较重,质地较硬,往往使医学放射学工作者背部、腰部肌肉十分劳累,甚至受到损伤,且价格昂贵,容易造成铅中毒。在这种发展趋势下,如何保护医护人员免受各种射线伤害,显得尤为重要。
随着非织造布的飞速发展,医用手术服也日新月异,防粘布、水刺布、SMS复合布及闪蒸等非织造布应运而生,应用到医用手术服上也各有优缺点,防粘布透气性差,有质感,静水压低,防护性差,但价格相对便宜,因此防粘布是我国制造手术服的主要非织造布面料。通常为了达到防护效果,手术服面料通常还要经过层压或复膜处理,厚重且透气性非常差;水刺布穿着起来最像传统机织物,柔软,悬垂性好,但水刺技术有限,用于手术服的水刺非织造布不多,水刺手术服一般从国外进口,价格很高,所以国内很少有医院使用水刺布手术服;SMS非织造布防护性能好,且强度及耐磨性也好,但在线复合的SMS成本很高,手感也较差;闪蒸布过滤性能好,但非常不均匀,而且也只有拥有垄断技术的杜邦公司和日本旭化成公司可以做,价格很高。
发明内容
本发明的目的在于提供一种重晶石医用防护服材料及其制备方法,本发明提供的重晶石医用防护服材料不仅兼具X射线防护功能和制备成本低的优势,还具有良好的透气及透湿性能,并且经洗涤和/或消毒后可以重复使用。
为达到上述目的,本发明采用以下技术方案来实现:一种重晶石医用防护服材料,由隔离层和外防护层构成,所述隔离层是由重晶石细粉末与聚乙烯按照重量比3.5:6.5或4:7.5均匀揉合加工制备而成,厚度为190~300μm;所述外防护层为丙纶纺粘无纺布,厚度为150~230μm;
所述重晶石细粉末中BaSO4含量≥98%;所述重晶石细粉末的粒径为1000~1250目;所述医用防护服材料的厚度为420~450μm。
本发明还提供了上述方案所述重晶石医用防护服材料的制备方法,包括以下步骤:
(1)选用湖南衡南重晶石矿,进行手选、重选和磁选物理提纯,得到BaSO4含量≥98%的重晶石;将所述重晶石进行磨粉,得到重晶石细粉末,粒径为1000~1250目;
(2)将步骤(1)所述重晶石细粉末与聚乙烯按照重量比3.5:6.5或4:7.5,均匀揉和,热压成型,得到隔离层非织造布;
(3)将步骤(2)所述隔离层非织造布与丙纶纺粘无纺布进行热轧复合,热轧温度控制在130~140℃,得到重晶石医用防护服材料。
优选的,所述步骤(2)热压成型的温度为105~120℃。
本发明提供的一种重晶石医用防护服材料将非织造布与非金属矿物中重晶石相结合,不仅保留了非织造布质地轻盈特点,还兼具X射线防护功能和制备成本低的优势,并且具有良好的透气及透湿性能,而且经洗涤和/或消毒后可重复使用。
本发明提供的制备方法工艺简单,制备成本低。
附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案,下面将对实施例中所需要使用的附图作简单地介绍,显而易见地,下面描述中的附图仅仅是本发明的一些实施例,对于本领域普通技术人员来讲,在不付出创造性劳动性的前提下,还可以根据这些附图获得其他的附图。
图1本发明重晶石医用防护服制备工艺流程图。
具体实施方式
为了进一步说明本发明,下面结合具体实施方式及附图对本发明作进一步的详细说明,但不能将它们理解为对本发明保护范围的限定。
实施例1:
一种重晶石医用防护服材料,包括隔离层和外防护层,其中,所述隔离层是由重晶石细粉末与聚乙烯按照重量比3.5:6.5均匀揉合加工制备而成,厚度为190μm,所述外防护层为丙纶纺粘无纺布,厚度为230μm。其中,制备方法包括以下步骤:
(1)原料制备:①选用湖南衡南重晶石矿,进行手选、重选和磁选物理提纯,得到BaSO4含量≥98%的重晶石;
②将步骤①制得的重晶石进行磨粉,磨粉粒径为1250目。
(2)隔离层制备:将步骤(1)制得的重晶石细粉末与聚乙烯按照重量比3.5:6.5,均匀揉和,在温度105℃下热压成型得到厚度为190μm的防护服隔离层非织造布。
(3)医用防护服材料制备:将步骤(2)制得的隔离层非织造布与丙纶纺粘无纺布进行热轧复合,热轧温度控制在130℃,最高不超过140℃。
上述制备方法中,所述步骤(3)选用的丙纶纺粘无纺布厚度为230μm,制得的医用防护服的厚度为420μm。
实施例2
一种重晶石医用防护服材料,包括隔离层和外防护层,其中,所述隔离层是由重晶石细粉末与聚乙烯按照重量比4:7.5均匀揉合加工制备而成,厚度为300μm,所述外防护层为丙纶纺粘无纺布,厚度为150μm。其中,制备方法包括以下步骤:
(1)原料制备:①选用湖南衡南重晶石矿,进行手选、重选和磁选物理提纯,得到BaSO4含量≥98%的重晶石;
②将步骤①制得的重晶石进行磨粉,磨粉粒径为1000目。
(2)隔离层制备:将步骤(1)制得的重晶石细粉末与聚乙烯按照重量比4:7.5,均匀揉和,在温度120℃下热压成型得到厚度为190μm的防护服隔离层非织造布。
(3)医用防护服材料制备:将步骤(2)制得的隔离层非织造布与丙纶纺粘无纺布进行热轧复合,热轧温度控制在135℃。
上述制备方法中,所述步骤(3)选用的丙纶纺粘无纺布的厚度为150μm,制得的医用防护服的厚度为450μm。
实施例1和2制得的重晶石医用防护服材料,待自然冷却后进行检验、剪裁成医用防护服成品。
将本发明制备的防护服与市面上其他医用防护服进行比较,见下表。
表1几种防护服性能对比
由上表可以看出,本发明制备的医用防辐射防护服各方面性能均优于市面产品,在拉伸强度、透气、透湿度和射线防护等方面都表现出很大的优势。
尽管上述实施例对本发明做出了详尽的描述,但它仅仅是本发明一部分实施例,而不是全部实施例,还可以根据本实施例在不经创造性前提下获得其他实施例,这些实施例都属于本发明保护范围。
Claims (3)
1.一种重晶石医用防护服材料,由隔离层和外防护层构成,其特征在于,所述隔离层是由重晶石细粉末与聚乙烯按照重量比3.5:6.5或4:7.5均匀揉合加工制备而成,厚度为190~300μm;所述外防护层为丙纶纺粘无纺布,厚度为150~230μm;
所述重晶石细粉末中BaSO4含量≥98%;所述重晶石细粉末的粒径为1000~1250目;所述医用防护服材料的厚度为420~450μm。
2.权利要求1所述重晶石医用防护服材料的制备方法,包括以下步骤:
(1)选用湖南衡南重晶石矿,进行手选、重选和磁选物理提纯,得到BaSO4含量≥98%的重晶石;将所述重晶石进行磨粉,得到重晶石细粉末,粒径为1000~1250目;
(2)将步骤(1)所述重晶石细粉末与聚乙烯按照重量比3.5:6.5或4:7.5,均匀揉和,热压成型,得到隔离层非织造布;
(3)将步骤(2)所述隔离层非织造布与丙纶纺粘无纺布进行热轧复合,热轧温度控制在130~140℃,得到重晶石医用防护服材料。
3.根据权利要求2所述的制备方法,其特征在于,所述步骤(2)热压成型的温度为105~120℃。
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