胶乳探空气球的充气量和长度与升空高度的关系

通过理论分析和试验验证,探讨了胶乳探空气球(简称探空气球)的充气量和长度与升空高度的关系。结果表明:采用相同规格的模型,在相同配方和工艺下生产的探空气球,其升空高度与充气量和长度成反比;充气量越大,探空气球升空高度越小,在保证上升速度的情况下充气量越小,探空气球升空高度越大;探空气球的长度越大,其升空高度越小,在伸张均匀的情况下,探空气球的长度越小,其升空高度越大。     

Preparation of Bi2O3@PCPA-KH590/chloroprene composites with good mechanical properties under high-filling

As a “green” radiation protection material with the potential to replace lead oxide, bismuth oxide has more research applications in the field of γ protection. However, due to their different surface properties, there are compatibility and interaction problems between metal oxides and rubber. To enhance the performance of bismuth oxide in neoprene, Bi₂O₃@PCPA-KH590 was prepared by coating bismuth oxide with polyphenol/polyamine and grafting KH590 on the surface of bismuth oxide. This allows for creating more active sites with the help of polyphenol/polyamine, enabling KH590 to be grafted onto bismuth oxide particles. The S functional group on the silane coupling agent is then cross-linked with the rubber substrate, enhancing the dispersibility of the bismuth oxide powder. This improvement not only improves the dispersibility of the bismuth oxide powder but also enhances the mechanical properties of the rubber composite material. Compared with pure CR, the mechanical properties of 60 wt% filler-modified powder composites can still be maintained at a high level, with the tensile strength reaching 12.83 Mpa. In sum, the proposed method appears feasible for preparing highly filled radiation protection rubber-based materials.     

mPE/LDPE交联物的流变性能研究

采用动态黏弹仪研究了不同配比的茂金属聚乙烯(mPE)/低密度聚乙烯(LDPE)交联物流变性能,发现因为mPE/LDPE二者之间可能存在的物理交联结构和交联物的网络结构,其微观结构具有更强的多分散性。     

微生物凝固天然橡胶的性能

采用从胶乳中分离、筛选出来的菌种凝固天然胶乳,制备微生物凝固天然橡胶(NR-m)。研究了NR-m的理化性能、热氧降解性能、硫化特性和硫化胶力学性能,并与酸凝固天然橡胶(NR-a)进行了对比。结果表明:与NR-a相比,NR-m的P0和灰分含量高,而挥发物含量、杂质含量、PRI、氮含量低,数均分子量(Mn)大,分子量分布(MWD)窄;混炼胶的最大扭矩值(MH)高,t10和t90短,硫化速率指数(Vc)大;硫化胶力学性能好,老化前、后性能变化较大;NR热氧降解可分为两个阶段,NR-m热氧降解的特征温度T0、TP和Tf均比NR-a低。