A new approach to fabricate polypropylene alloy with excellent low-temperature toughness and balanced toughness-rigidity through unmatched thermal expansion coefficients between components

Polymer ◽  
2017 ◽  
Vol 112 ◽  
pp. 318-324 ◽  
Author(s):  
Yonggang Shangguan ◽  
Feng Chen ◽  
Jie Yang ◽  
Erwen Jia ◽  
Qiang Zheng
2019 ◽  
Vol 39 (10) ◽  
pp. 902-908
Author(s):  
Xueqiang Zhang ◽  
Zepeng Mao ◽  
Jun Zhang

Abstract In this study, poly(vinyl chloride) (PVC)/acrylonitrile-styrene-acrylic terpolymer (ASA)/acrylonitrile-butadiene rubber (NBR) ternary blends were designed based on the concept of mismatched thermal expansion coefficient between different components, resulting in significant improvement of the low-temperature toughness. The large difference in thermal expansion coefficients strengthened the interfacial tensile force (i.e. negative pressure) on NBR phase and reduced its glass transition temperature (Tg) by nearly 20°C, which was attributed to the improvement in the free volume of NBR. As a result, the low-temperature toughness of PVC/ASA/NBR ternary blends improved significantly. With the incorporation of 12.5 phr NBR in the PVC/ASA (100/15, w/w) matrix, the blends could achieve the highest impact strength of 76.2 kJ/m2 at 0°C and 10.7 kJ/m2 at −30°C. Simultaneously, the brittle-ductile transition (BDT) of the toughness shifted to the high NBR content region with the decrease of temperature. However, the improvement in the toughness of PVC/ASA/NBR ternary blends was at the expense of a decrease in rigidity.


2016 ◽  
Vol 30 (11) ◽  
pp. 1650127 ◽  
Author(s):  
Yi Ren ◽  
Wen Ma ◽  
Xiaoying Li ◽  
Jun Wang ◽  
Yu Bai ◽  
...  

The SOFC interconnect materials La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] [Formula: see text]–[Formula: see text] were prepared using an auto-ignition process. The influences of Cr deficiency on their sintering, thermal expansion and electrical properties were investigated. All the samples were pure perovskite phase after sintering at 1400[Formula: see text]C for 4 h. The cell volume of La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] decreased with increasing Cr deficient content. The relative density of the sintered bulk samples increased from 93.2% [Formula: see text] to a maximum value of 94.7% [Formula: see text] and then decreased to 87.7% [Formula: see text]. The thermal expansion coefficients of the sintered bulk samples were in the range of [Formula: see text]–[Formula: see text] (30–1000[Formula: see text]C), which are compatible with that of YSZ. Among the investigated samples, the sample with 0.02 Cr deficiency had a maximum conductivity of 40.4 Scm[Formula: see text] and the lowest Seebeck coefficient of 154.8 [Formula: see text]VK[Formula: see text] at 850[Formula: see text]C in pure He. The experimental results indicate that La[Formula: see text]Sr[Formula: see text]Cr[Formula: see text]O[Formula: see text] has the best properties and is much suitable for SOFC interconnect material application.


2006 ◽  
Vol 947 ◽  
Author(s):  
Kyung Choi

ABSTRACTHigh resolution pattern transfers in the nano-scale regime have been considerable challenges in ‘soft lithography’ to achieve nanodevices with enhanced performances. In this technology, the resolution of pattern integrations is significantly rely on the materials' properties of polydimethylsiloxane (PDMS) stamps. Since commercial PDMS stamps have shown limitations in nano-scale resolution soft lithography due to their low physical toughness and high thermal expansion coefficients, we developed stiffer, photocured PDMS silicon elastomers designed, specifically for nano-sized soft lithography and photopatternable nanofabrications.


1985 ◽  
Vol 82 (3) ◽  
pp. 1611-1612 ◽  
Author(s):  
Stanley L. Segel ◽  
H. Karlsson ◽  
T. Gustavson ◽  
K. Edstrom

Sign in / Sign up

Export Citation Format

Share Document