17 Jun 2008

The TPU one is synthetic

Submitted by super

.The TPU one is synthetic
  TPU can be divided into a footwork and gathered the law in advance while formating the method, because response conditions are different, greater difference appears in the performance of the polymer. Among them the best method is that a footwork uses one pair of spiral shells' pole pushing out of machine to produce TPU. TPU had to a step legal system, it is one kind that inlays a section of line type polymer basically, the basic response type is:
 2nOCN-R-NCO+nHO-R'-OH+nHO-R" -OH CONH-R-NHCOO-R'-O-CONH-R-NHCOO-R" -On
  Adopt pairs of spiral shell pole person who push out of formate TPU in succession, craft its step to prepare, is it transport, is it react, is it build by raw materials 4 parts make up to push out of to mix to measure.
Craft this have raw materials matching measure accurate mixing even reacting temperature one and supplies the time of staying characteristic such as being even in machine. But in the technological process, the control on raw materials moisture, precision, transport, temperature profile and cutting a technology of measurement can't be ignored <1>. According to the need, through the adjustment of filling a prescription, can design products of TPU with suitable performance indicator. The formation of TPU is a system engineering, grasp every key element, can make the satisfactory result.: TPU formates the craft and studies the tendency, should focus on and improve its physics mechanical performance and heat-resisting performance.
2.Application and development of TPU
  TPU, because performance is excellent, deeply by the narrowing bluly and greenly of people, application of it permeate through each industrial field nearly, building, car making for instance, take precautions against earthquakes padded coaming, decorate material, field of processing hides etc., Dr.eye: and a lot of potential fields remain to open up.
2.1.In the industrial application of textile
  Application in textile of TPU, mainly adopt the melting law to spin the ammonia black silk ribbon, has launched <2 jobs in this respect too at home >. At present, it is to rely mainly on doing the law that the ammonia black silk ribbon produces the majority in the world, the output of black silk ribbon of ammonia of American E. Dr.eye: I. Dr.eye: Du Pont de Nemours & Company accounts for over half of the output of black silk ribbon of world ammonia. Is it do law ammonia that spinning produce black silk ribbon of good performance, invest in too high to adopt (whether factory, annual output of 500 t nearly need to invest 200 million yuan) ,Payback period of investment is long, the production cost is relatively high too, and the question exists and pollutes the environment, detrimental to health. And melt and spin the law and produce the ammonia black silk ribbon and have advantages of investing in less, with low costs, pollution-free to the environment etc., Dr.eye: and can utilize the melting and spinning equipment of existing other fibres, does not need to make and change and upgrade the ammonia black silk ribbon that the equipment can produce ordinary quality greatly, have better economic benefits. Our country in development and is it have report to study of field this, industry nature ammonia black silk ribbon is it is it make kind result very also to spin to try. Melt and spin the ammonia black silk ribbon and do the difference of ammonia black silk ribbon performance of the law to narrow. Melt and spin one of the main production methods that the law will become the ammonia black silk ribbon.
  At present, have melted the extending rate which is spun the ammonia black silk ribbon and already reached and done France's level, it draw intensity higher than do law ammonia black silk ribbon obviously, do law ammonia black silk ribbon spin ammonia black silk ribbon have a better one to be little to separate degree and hard district stabilities melting, have determined that disparity exists on the resuming rate of elasticity to melt and spin the ammonia black silk ribbon. So, if after handing in and uniting dealing with in chemistry, the fibre can get obvious improvement back to the elasticity. Melt and spin the ammonia black silk ribbon craft roughly in a footwork, two footwork, seal four respects of the end law and direct method and have <2, 3, 7 reports >.
 Someone optimized and filled a prescription once by melting and spinning a footwork, in case of not adding any additive, fine Wei of black silk ribbon of ammonia made draws intensity 1.3 cN/dtex, rupturing and extending rate is 729.1%. Of our country Shenzhen new black silk ribbon Company adopt two ammonia black silk ribbon fine Wei that legal system become draw intensity 1.6 cN/dtex, rupture 600% of extending etc., 300% stretches 97% of resuming rate definitely. Even so, our country, to melting the research of spinning the law ammonia black silk ribbon, the not enough system and deepenning.
With among the course, little to separate formation mechanism, dynamics, spinning further investigation, shaping of performance of structure to spinning, will perfect and melt the craft of spinning further, thus produce the ammonia black silk ribbon with excellent performance, this will play a very big role to that our country melts the development which is spun ammonia black silk ribbon industry.
 Ammonia black silk ribbon new variety development field focus on original silk new variety, for example in chlorine of able to bearing, able to bear hydrolysising, be heat-resisting, able to bear the tide, able to bear the mould and fire-retardant respecting. In processing, ammonia black silk ribbon can with wait for fibre is it is it reply or wrap to wrap up to go on by nylon, dyeability, mechanical intensity and wearability its fine. Make core silk with the ammonia black silk ribbon, wrap the spiral type with the silk outside, can improve the product specification of pure silk, increase the competitiveness in the international market of products of silk of our country. Adopt the textile yarn and ammonia black silk ribbon to process into the bag core yarn, after exactly dyeing and processing, cloth cover pass to elastic, high-elastic cowherd cloth and well received by consumer even corduroy developed.
 2.2.Automobile bumper
 
Form 1 TPU compares with bumper performance of PP-EPDM material

Material
TPU
PP-EPDM

Draw the intensity / MPa
55~60
18~28
Turn into a mould amount / MPa
3000~3100
600
Izod assaults the intensity / J.m-1
1000~1200
600

The hot temperature out of shape / degrees Centigrade
90~95
85

Density / g.cm-3
0.90~0.92
0.91~0.92

 
 Note: TPU bumper is developed by Shenyang chemical engineering institute; PP-EPDM bumper, in order to use both at home and abroad
Have now products.
  TPU can be applied to many kinds of components of the automobile car body, for instance such spare parts as the bumper, instrument board, shock attenuation cushion,etc.. The automobile bumper generally and strengthens the roof beam to make up by each. Domestic and international bumpers are mostly the polypropylene ( PP) With third rubber of second ( EPDM) Mix the thing material altogether. There are patent reports <8>, use bumper that TPU make, is it collide and striking testing with whom speed of 400 km/h go on to go through successively, with breaking again with more than 60 times 10 kg sledge hammers, have not found that obviously break, has proved its safe performance is very high, can reduce the vehicle and damage the degree and casualties in the accident. This bumper of production costs are relatively low, worth developing. TPU elastomer material and PP-EPDM mix performance of material see forms 1 altogether.
 Our country will enter WTO soon, the automobile trade must have new characteristics can establish in an unassailable position. Developing has bumpers with high safe performance, should bring party's concerned attention.
 2.3.The rail rests the head on the backing board
 The sleeper backing board used in domestic and international railway, its comprehensive performance is still the weak point, it is short-lived to use, has influenced the speed-raising of the train and comprehensive facility to form a complete set. Patent report <10>, adding the sleeper backing board that made of low-priced packing in TPU, performance is superior to the rubber backing board, but larger limit absorbs the impact pressure to the rail and road bed of train going, thus in increase train draw power, transform road bed, is it park situation of website to reduce, make train achieve the goal of raising speed, driving speed can bring 250 km/h up to to be the above-mentioned. The test result indicates, the backing board of new-type sleeper does not have any interference to the command system of the communication of the railway, it wear and tear indicator to be backing board 10 time low than rubber, service life improve greatly, reduce backing board change the number of times, reduce and change the expenses, it is of good performance to synthesize.
2.4.TPU application and development in aviation industry
Block network is it prevent plane from take off or is it slip when running is it go out the runway to meet accidenting to land to use for, and guarantee the security of the aircrew and plane, prevent the great accident from happenning. Foreign airport block network is it make to weave by nylon mostly. Our country adopts and pushes for raw materials out of the net of blocking made of the method with TPU, have intensity heavy, light, fine difficult and mildew and rot is it tear, able to bear low temperature, able to bear oil fine performance such as being of good performance to able to bearing elasticity. Add the network physical stamina that make of fluorescence material to give out light in the evening in the raw materials of TPU. Its various kinds of performance are superior to the network body woven with nylon in the world. For example the vertical area that nylon weaves, it draw intensity as 139.2 MPa, with whom TPU make being vertical to lead the intensity of drawing for 186.3 MPa. Therefore TPU can apply to block the network at the airport. Is it block network can is it protect and blocking in expressway or sky way dangerous location to use as also to it's time.
 The fuel tank of thin wall of plane made of TPU, not only the craft is simple, and the wall is thin, light, have long performance life. TPU has higher resisting radiation, is suitable for producing to universe aircrew, X ray and atomic energy staff members' protection clothing.
  As the aviation undertaking is being developed constantly, increase to the plane maintenance technology demand correspondingly too, at the same time to restore demand of technology too strict, is it compress gasbag made of TPU that air inflates redound technology to adopt, can meet the demand of the above.
  2.5.Cable overcoat
  Used in to float cable, optical cable, earthquake cable, sheath, plane of cable can is it succeed to process with TPU generally sea floor,etc., Dr.eye: able to bear hydrolysising, able to bear waiting, be wear-resisting, able to bear such advantages as song scratching, high hardness,etc.inging at the same time because of its resistivity 1012¦¸ cm of volume, TPU makes the cable, electric wire overcoat, not only the electricity is insulating and of good performance, but also have very easy performance of protecting to the conductor, using the security, it is difficult to cause the unexpected fire accident.