文档详情

5橡胶工艺学第四章橡胶补强与填充体系.pptx

发布:2021-05-15约字共81页下载文档
文本预览下载声明
第三章 橡胶的补强与填充体系 第一节 概述 补强剂与填充剂统称填料,起提高各项力学性能,降低成本的作用。 炭黑是橡胶工业中最重要的补强性填料,其耗量约占橡胶耗量的一半。无机填料的用量已和炭黑用量相当。 一次结构粒径、形态、表面活性等填料性质对于填充聚合物体系的加工性能和成品性能具有决定性的影响。 1.补强与填充的重要性: 橡胶工业用的补强剂是炭黑和白炭黑。 炭黑可以使橡胶的强度提高约10倍。 炭黑对橡胶的补强效果 胶种 未补强 的拉伸强度/MPa 炭黑补强 的拉伸强度/MPa SBR 2.5-3.5 20-26 NBR 2.0-3.0 20-27 EPDM 3.0-6.0 18-25 BR 8.0-10.0 18-25 NR 16.0-24.0 24-35 填充可起到增大体积,降低成本,改善加工工艺性能,如减少半成品收缩率、提高硫化胶硬度。 常用的有陶土,碳酸钙,滑石粉等。 2.填料的分类: 第二节 炭黑的品种与性质 一.品种及分类: ASTM D1765 (Rubber Standards) Standard Classification System for Carbon Blacks Used in Rubber Products 1. Scope 1.1 This classification system covers the classification of rubber-grade carbon blacks by the use of a four-character nomenclature system. The first character gives some indication of the influence of the carbon black on the rate of cure of a typical rubber compound containing the black. The second character gives information on the average surface area of the carbon black. The last two characters are assigned arbitrarily. 1.2 All rubber-grade carbon blacks for which a number is currently assigned at the time of publication of this classification system are listed in Table 1 together with some of their typical properties. ASTM classification numbers (“N” or “S” designation) not listed in Table 1 have either been withdrawn or are not currently assigned. The use of inactive or unassigned N or S designations is prohibited until such a time as the designation is officially reactivated or assigned by Subcommittee D24.41 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 接触法炭黑 炉法炭黑 热裂法炭黑 新工艺炭黑 Ⅰ.按制造方法分 ⑴.接触法炭黑: 把原料气燃烧的火焰同温度较低的收集面接触,使不完全燃烧的炭黑冷却并附着在收集面上,再加以收集。 包括槽法炭黑,
显示全部
相似文档