Yas thiab cov roj hmab muaj cov ntaub ntawv polymer, tsuas yog muaj cov pa roj carbon thiab hydrogen, thiab qee tus muaj cov pa roj oxygen me me, thiab txhua yam, cov tshuaj lom neeg, cov leeg sulfur thiab lwm yam atoms. Lawv muaj cov khoom tshwj xeeb thiab siv tau. Nyob rau hauv chav tsev kub, yas yog khoom, heev zog, thiab tsis tuaj yeem ncab lossis deformed. Roj hmab tsis nyuaj heev, ywj, tuaj yeem ncab thiab elongated, thiab tuaj yeem rov qab mus rau nws cov qauv qub thaum lub teeb ncab. Qhov no yog vim lawv cov qauv sib txawv. Lwm qhov sib txawv yog tias cov yas tuaj yeem rov ua dua tshiab thiab siv ntau zaus, thaum siv roj hmab tsis tuaj yeem kho ncaj qha. Nws tsuas yog ua tiav rau cov roj hmab rov ua dua ua ntej nws tuaj yeem siv, yog li koj tuaj yeem nkag siab lawv txoj kev sib raug zoo thaum koj pom qhov no. Roj Hmab tau siv dav siv vim nws cov yam ntxwv. Ua ntej tshaj plaws,
① Thermal conductivity roj hmab yog ib tug neeg ua neeg coj ua ntawm tshav kub. Nws cov thermal conductivity yog hais txog 2.2 ~ 6.28 w / m2 {5}} k thaum lub tuab yog 25 hli. Nws yog ib qho zoo heev thermal rwb thaiv tsev cov khoom. Yog tias cov roj hmab tau tsim rau hauv lub microporous lossis daim txhuam cev lub xeev, nws cov thermal conduction yuav ua rau muaj kev kub ntxhov, yog li kev saib xyuas kom sov thaum tshav kub kub.
② Thermal expansion Since there is a large free volume between rubber molecular chains, when the temperature rises, the internal rotation of its chain segments becomes easier, which will increase its volume. The linear expansion coefficient of rubber is about 20 times that of steel. This must be taken into account in the design of the vulcanization model of rubber products, because the linear size of the finished rubber product will be 1.2~3.5% smaller than the model. For the same type of rubber, the hardness and raw rubber content of the rubber compound also have a great influence on the shrinkage rate of the rubber compound. The shrinkage rate is inversely proportional to the hardness and directly proportional to the rubber content. The theoretical shrinkage rate of various rubbers is in the following order: fluororubber>silicone rubber>butyl rubber>nitrile rubber>chloroprene rubber>styrene-butadiene rubber>Yog vim li cas roj hmab yog vim li cas roj hmab yog xaiv raws li cov khoom siv raw hauv cov yeeb nkab fittings. Nyob rau ib lub sijhawm thaum kev lag luam roj hmab yog tsim sai sai hnub no, kev muag khoom ntawm lub ntiaj teb kev lag luam roj hmab tau tshaj li $ 250 lab cov khoom lag luam tau ntev dhau los ua ib qho tseem ceeb hauv kev lag luam thoob ntiaj teb. Hauv kev ua lag luam hauv ntiaj teb, cov khoom lag luam tau tsim cov khoom lag luam khoom lag luam thiab cov khoom siv roj hmab, nrog rau cov roj hmab niaj hnub xws li kev kho mob, kab lis kev cai thiab kis las.