The Jinghu system made Lu Wenhuan reluctant to deal with Li Wen Tianxiang, but thinking that this guy was still a little famous, and considering the entrustment of the old leader Jia Pingzhang, he had to provide him with a convenience.

At that time, he happened to have a batch of eucommia bark, roots, branches, dried leaves, and some gypsum to be sent to Liuqiu Island, so he might as well add one or two more boats to send Wen Tianxiang as a personal favor.

At the same time, he wrote a letter for Wen Tianxiang to take and send to Zhang Islander, which can be regarded as a letter of introduction, so as not to be too abrupt.

Five hundred good laborers were not left, and the Jinghu system made Lu Wenhuan feel distressed!

He knew what kind of eucommia rubber produced on Liuqiu Island was conjured from the eucommia tree, and he also asked his craftsmen to try to change it, but the result was always in vain, so he resigned himself to his fate, maybe the owner of Zhang Island really could cast spells as rumored.

Fortunately, the leaves and branches of the eucommia trees can be sold for money, and as long as the method is done properly, the annual output is still quite a lot.

He had already ordered people to plant vigorously in the nearby mountains, and it did not occupy the fields anyway.

In the end, Wen Tianxiang was sent away, and they left------ I can't say that this stunned young man can convince the owner of Zhang? !

That's an unexpected bonus.

Wen Tianxiang took his five hundred townsmen on the boat, and then went all the way down the river.

Wen Tianxiang was also very curious about how Liuqiu Island could get any Eucommia rubber from the Eucommia trees----- but he had seen some large families buy four-wheeled carriages with two-finger-thick Eucommia rubber wrapped in the wheels.

I've also seen the so-called Eucommia ulmoides rubber sole sail step fast shoes------ this thing is really useful!

Otherwise, there wouldn't have been so many messages of receiving Eucommia ulmoides on the wide advertisement of the "Liuqiu Times", and they even wanted branches and leaves, which is really a good thing, and it will give the people of the Great Song Dynasty another income!

He thought of Liuqiu Island even more heartily, but he couldn't fly there------

The owner of Zhang Island did buy Eucommia ulmoides in large quantities, and listed it as a major planting item on Liuqiu Island, along with the Indian rubber banyan tree.

Eucommia ulmoides was widely distributed in Eurasia before the Late Tertiary.

When the Quaternary Ice Age came, Eucommia ulmoides disappeared in Europe and other regions, and only the Great Song Dynasty became the main survivor of Eucommia ulmoides in the world due to the blockage of glaciers due to the complex terrain.

The Eucommia ulmoides tree in the territory of the Great Song Dynasty has the characteristics of cold resistance, drought resistance, thin ridge adaptation, rapid growth, etc., and is widely distributed in all parts of the territory, and there are many wild ones.

Zhang regarded it as one of the materials to replace natural rubber first------ but it is still different from natural rubber.

First of all, the main component of traditional natural rubber is cis-1.4-polyisoprene, while the main component of eucommia gum is trans-1.4-polyisoprene, which have very different physical properties.

Eucommia ulmoides rubber has rubber and plastic duality, good insulation, water resistance, corrosion resistance, but the disadvantage is that the elasticity is very poor, the heat resistance is poor, and it will be deformed if it is more than 50 degrees------- it is generally used to manufacture hard rubber products, and if it is used as a material for the production of automobile tires, it itself is "congenitally insufficient".

Of course, with the progress of technology, polymer technology, new processes and synthesis technologies have been used to manufacture highly elastic materials from trans rubber, which has the possibility of solving the problems of tire strength, tire life, tire friction and heat release, etc., but the energy consumed here is no less than transforming ordinary bricks into refractory bricks.

In that world, there have been people who have used this to pull investment------ in fact this is a scam, the output of eucommia gum is far less than the natural rubber that can be harvested in twelve months, not to mention, the cost of new synthetic technology is seven or eight times the cost of natural rubber, and it is not practical at all.

But in this world, cost is the least of a problem for Zhang Island------ the people of the Great Song Dynasty will only use it as a general Chinese medicine, and no one can compete with him!

The process of extracting Du rubber is relatively simple, and the equipment requirements are relatively low------ of course, this is for Zhang Island and Wang Defa's family.

They first used the pot camel machine as the power to crush the roots, bark, branches and dried leaves of Eucommia ulmoides that had been prepared, and then soaked in a ceramic reactor with a concentration of 15% caustic soda, slowly heated, and when the temperature reached 90 degrees, the temperature was controlled until about three hours.

After that, stop heating, let it cool naturally, then soak it with a wire spoon, transfer it to another ceramic reactor, soak it with 30% concentration of hydrochloric acid, and keep it at a constant temperature for 24 hours when it is heated to 40 degrees Celsius before leaching.

Finally, it is quickly dried in a dryer.

The results showed that the glue yield of Eucommia ulmoides was 14% and the glue content was 65%.

The colloidal gel is loose and incorrectly colored, but it is very flexible and easy to vulcanize and thermoform.

In Zhang's rubber factory, there are nearly 2,000 workers doing such repetitive work, and the daily output of 20 tons of Eucommia ulmoides rubber is not enough!

The method of extracting rubber from Indian rubber ficus is about the same, but the glue content is lower.

Fortunately, this rubber tree was easier to grow and grew faster, so it was easily introduced from India.

Of course, Zhang knows that these two kinds of rubber are not resistant to high temperatures----- but with the driving force of this time and space, where can the temperature of solid tire friction reach more than 50 degrees?!

Of course, he won't use it as a high-temperature gasket anymore, brass gaskets seal better than rubber gaskets!

The cultivation of sugar beet really can't hide the shrewd merchants of the Great Song Dynasty, I believe that sooner or later they will use various local methods to solve the whiteness of sugar------ but they really can't rubber, except for their own domestic boys, no one in this world can know the method of large-scale production of hydrochloric acid.

Of course, the use of rubber is not only as simple as making solid tires and soles------ so sooner or later it will be a big killer to earn all kinds of materials and manpower in the Great Song Dynasty!

Similar to techniques such as glass and mirrors, the owners of Zhang Island were all blocked from the outside world------ didn't the official kilns of the Great Song Dynasty do the same to them, and the craftsmen there never taught the kiln firing techniques of Liuqiu Island.

On the one hand, the island can only produce a small amount of expensive bone china, and on the other hand, it can only produce a large amount of coarse porcelain that is not valuable.

Wen Tianxiang was born in a water town, and he has also been to sea, he is not afraid of wind and waves at all, and reads all kinds of newspapers he bought before going to sea in the cabin all day long.

The variety of newspapers of the Great Song Dynasty and Liuqiu Island is growing day by day, but some of them are beautifully printed and some are crude.

In the afternoon of that day, he suddenly heard the bow of the steward shouting: "Everyone, pay attention, the coast guard has come to inspect it, deal with it carefully, and make no mistakes!"

He put down the newspaper and went out of the hatch to read.

He saw two two-masted ships with black smoke speeding in the distance, and they really didn't hang their sails and were moving at high speed!

The big blue flag flying high on the mast fluttered in the wind------

They don't look the same as ordinary sailboats, they have a slightly flat bow and what appears to be a cannon on it!

When they got closer, they could be seen with Haijing No. 121 and No. 122 written in white oil on the side of their ship------ Wen Tianxiang certainly knew that it was the number of Liuqiu Island.

On the Haijing No. 121, an officer wearing a light blue military uniform, a round cap, and two shoulders that seemed to have yellow epaulettes on his shoulders raised the iron horn in his hand and shouted:

"Please stop the ship and drop the sails, and beg the coast guard to inspect it!"

Wen Tianxiang saw that there were more than a dozen soldiers on the boat who were also wearing light blue military uniforms, each of them holding sharp short spears in their hands, all with serious expressions!

The bow of the ship greeted warmly: "Officer Chen, don't worry, this is the Lu family's fleet!" ”