【摘要】：短切炭纖維可通過粘結(jié)劑粘結(jié)、炭化制得炭纖維網(wǎng)絡(luò)結(jié)構(gòu),有關(guān)粘結(jié)短切炭纖維成型材料的研究已有很多報(bào)道,包括保溫材料及吸附分離材料等,但這些研究都沒有把多孔的、成塊的的作為增強(qiáng)體進(jìn)一步復(fù)合制成材料,所以本文在炭纖維粘結(jié)體的基礎(chǔ)上與樹脂復(fù)合制得材料并進(jìn)一步研究其性能。本實(shí)驗(yàn)以短切炭纖維為原料,通過預(yù)先制成炭纖維網(wǎng)絡(luò)增強(qiáng)體(Carbon fiber network reinforcement,CFNR),然后浸膠環(huán)氧樹脂和聚丙烯制得剛性好、熱膨脹低的網(wǎng)絡(luò)增強(qiáng)環(huán)氧樹脂和聚丙烯的新型復(fù)合材料。利用掃描電鏡和熱機(jī)械分析儀對(duì)試樣的微觀結(jié)構(gòu)和熱機(jī)械性能進(jìn)行表征分析。結(jié)果表明,CFNR中觀察到了明顯的網(wǎng)絡(luò)節(jié)點(diǎn),即炭質(zhì)粘結(jié)點(diǎn)。網(wǎng)絡(luò)增強(qiáng)環(huán)氧樹脂復(fù)合材料的彎曲模量最高,是常規(guī)短切炭纖維/環(huán)氧樹脂復(fù)合材料的近3倍,純環(huán)氧樹脂的6倍;高溫承載時(shí),三種試樣彎曲模量因環(huán)氧樹脂變軟而降低:溫度高于80℃時(shí),CFNR/環(huán)氧樹脂復(fù)合材料彎曲模量約是短切炭纖維/復(fù)合材料的7倍,純環(huán)氧樹脂的近70倍。此外,CFNR/環(huán)氧樹脂復(fù)合材料有良好的導(dǎo)電性和熱尺寸穩(wěn)定性,其熱膨脹系數(shù)(60-200℃)最小,純環(huán)氧樹脂相應(yīng)的平均熱膨脹系數(shù)是它的13倍,短切炭纖維/環(huán)氧樹脂復(fù)合材料是它的5倍左右。網(wǎng)絡(luò)增強(qiáng)環(huán)氧樹脂復(fù)合材料具有最高的儲(chǔ)能模量,短切炭纖維/環(huán)氧樹脂次之,環(huán)氧樹脂最小,隨著溫度升高,儲(chǔ)能模量都降低,最終達(dá)到一個(gè)穩(wěn)定值。短切炭纖維/環(huán)氧樹脂復(fù)合材料的玻璃化轉(zhuǎn)變溫度最高,環(huán)氧樹脂最低,網(wǎng)絡(luò)增強(qiáng)環(huán)氧樹脂復(fù)合材料位于兩者之間。炭纖維上漿后制備的網(wǎng)絡(luò)增強(qiáng)環(huán)氧樹脂復(fù)合材料其彎曲模量、儲(chǔ)能模量和玻璃化轉(zhuǎn)變溫度均比未上漿的炭纖維所制備的復(fù)合材料要高。通過SEM觀察CFNR/聚丙烯復(fù)合材料的斷面可以發(fā)現(xiàn)纖維粘結(jié)在一起的節(jié)點(diǎn)。常溫時(shí)在相同載荷下,聚丙烯的行變量最大,是CFNR/聚丙烯復(fù)合材料的2.4倍,短切炭纖維/聚丙烯復(fù)合材料的形變量次之,是CFNR/聚丙烯復(fù)合材料的1.5倍。常溫下CFNR/聚丙烯復(fù)合材料的彎曲模量分別約是常規(guī)短切炭纖維/聚丙烯復(fù)合材料及純聚丙烯的1.6倍和6倍,平均熱膨脹系數(shù)(60-120℃)分別是常規(guī)短切炭纖維/聚丙烯復(fù)合材料及純聚丙烯的1/4和1/5。隨著溫度升高,三種材料彎曲模量降低,聚丙烯在100℃以后彎曲模量變的較小,基本上在100MPa以下。短切炭纖維/聚丙烯復(fù)合材料在100℃后彎曲模量變化不大,彎曲模量大約在200MPa,CFNR/聚丙烯材料彎曲模量絕對(duì)值遠(yuǎn)高于前兩者,在400MPa以上。
[Abstract]:The network structure of carbon fibers can be obtained by binder bonding and carbonization of short cut carbon fibers. There have been many reports on bonding short cut carbon fiber forming materials, including thermal insulation materials and adsorptive separation materials, but none of these studies have made porous carbon fibers. The block is used as the reinforcer to make the material further, so the material is made from the carbon fiber binder and the resin, and its properties are further studied in this paper. In this experiment, short cut carbon fiber was used as raw material, carbon fiber network reinforcement (Carbon fiber network reinforcement,CFNR) was prepared in advance, and then impregnated with epoxy resin and polypropylene made of good rigidity. Low thermal expansion of the network reinforced epoxy resin and polypropylene new composite materials. The microstructure and thermal mechanical properties of the samples were characterized by SEM and TMA. The results show that obvious network nodes, that is, carbon bond point, are observed in CFNR. The flexural modulus of the network reinforced epoxy resin composite is the highest, which is about 3 times of that of the conventional short cut carbon fiber / epoxy resin composite and 6 times of that of the pure epoxy resin. At high temperature, the flexural modulus of the three specimens is reduced by the softening of epoxy resin. When the temperature is higher than 80 鈩，

本文編號(hào)：2355704