EFFECT OF IRRADIATION ON DIELECTRIC BEHAVIOR OF POLYETHERKETONE WITH CARDO GROUP

It is found in this paper that the dielectric behavior of polyetherketone with cardo group (PEK- C) irradiated at a dose of 2.02 MGy has an obvious change. For the irradiated PEK-C, both the temperature spectrum of dielectric loss factor (ε " ) within a range of 20-200 ℃ and the frequency spectrum of dielectric coefficient (ε') in a range of 30 Hz-1 MHz show that ε" and ε' increase from 5.4×10-3 to 4.6×10-1 andfrom 3 to 5, respectively.     

氯磺化聚乙稀的辐射交联

本文报道了三种不同氯含量的氯磺化聚乙烯(CSM)的辐射交联。同时,研究了CSM的结构和性能。X—射线衍射分析表明CSM是非晶态聚合物。红外光谱分析检测到CSM具有SO_2Cl,CCl和SO_3等基因。由于存在SO_2Cl和CCl基因使GM经~(80)Coγ—射线辐照后很容易交联。例如,40型CSM在70KGy剂量辐照后,凝胶含量已达60％。辐射交联后,CSM的抗张强度在一定剂量范围内有了明显地提高,当剂量为105KGy时,抗张强度最大。研究了力学性能与辐照剂量的关系。从-180至100℃范围内考察了CSM的介电松弛与转变,讨论了介电常数(ε′)和介电损耗因子(ε″)与温度的关系。从差示扫描量热(DSC)谱图上发现CSM的玻璃化转变温度(Tg)随氯含量增加而升高,辐照后Tg几乎没有变化。     

硅太阳能电池剂量仪

1962年Muller发表了硅太阳能电池剂量仪的报告,引起了辐射化学工作者很大的兴趣。研究半导体的辐射效应,以及利用太阳能电池作为辐射剂量仪,在理论上和实践上都有重要意义。本文报导了硅太阳能电池的辐射效应及用它测量~(60)Co源γ射线剂量率的一些结果。     

EFFECT OF γ-RADIATION ON PROPERTIES OF CHLORO-SULFONATED POLYETHYLENE

The effects of γ-radiation on three chloro-sulfonated polyethylene (CSM) with different chlorine content have been investigated, the effects of γ-radiation on some physical properties of CSM have been discussed. The results showed that three CSM can be easily crosslinked by irradiation, the crosslinking degree related to chlorine content, at the same radiation dose, the more the chlorine content in CSM, the easier the CSM to be crosslinked, unirradiated CSM has good mechanical properties (tensile strength and elongation), the effect of irradiation dose on dielectric properties was insignificant.     

辐照三聚甲醛及其聚合物的介电谱

本文报道了用介电谱法研究经γ射线辐照后固态三聚甲醛及其聚合物的分子运动和结构转变。发现三聚甲醛在45～52℃之间有一结构(晶格缺陷)变化。当温度升高时,陷落在这一缺陷中辐照产生的活性粒子(R~+)发生释放和复合。由于极性和分子运动的减弱,聚合后体系的介电损耗角正切值(tgδ)远远低于未辐照的三聚甲醛的tgδ。从tgδ与温度(T)的关系谱图上观察到单体转变为聚合物以及聚甲醛(POM)发生辐射裂解导致的分子结构的变化。     

Υ—辐射交联LDPE的物理性能(摘要)

本文研究γ—辐射交联LDPE的力学、介电和热性能,同时讨论其动态力学性能。结果表明:经250KGy剂量辐照后,抗张强度接近极大,约20Pa,而伸长率在50KGy左右剂量出现极大值,辐照交联后,tanδ略有增加,但在1kHz以内,室温下仍为10~(-4),ε在22左右,热学参数随剂量增加而下降。辐照交联后LDPE的贮能模量增加,多重转变温度Tα、Tβ和Tγ向高温方向移动,松弛强度有一定变化。图3表2参4