KR-20260065248-A - Rubber packing composition for ship with excellent low-temperature flexibility and water-pressure tightness suitable for polar environmen

Abstract

The present invention relates to a marine rubber packing composition having excellent low-temperature flexibility and hydraulic tightness suitable for polar environments. More specifically, the invention relates to a marine rubber packing composition used in polar environments that provides cryogenic flexibility by lowering the glass transition temperature through the use of NBR with a low acrylonitrile content, and to a marine rubber packing composition having excellent durability and hydraulic tightness suitable for polar environments by using surface-modified acetylene black as an additive to improve durability, thereby imparting intramolecular hydrogen bonds and ionic bonds and increasing the crosslinking density to minimize the reduction in elasticity even in cryogenic environments.

Inventors

• 강태희
• 이상철
• 김관용

Assignees

• 대명테크 주식회사
• 한국소재융합연구원

Dates

Publication Date

20260508

Application Date

20241101

Claims (3)

1. A marine rubber packing composition having excellent low-temperature flexibility and hydraulic tightness suitable for polar environments, characterized by comprising, per 100 parts by weight of NBR, 65 to 75 parts by weight of acetylene black, 12.5 to 13.5 parts by weight of process oil, 35 to 45 parts by weight of plasticizer, 2 to 3 parts by weight of anti-aging agent, 14 to 15 parts by weight of talc, 5 to 6 parts by weight of metal oxide, 1 to 2 parts by weight of softener, 1.5 to 2.5 parts by weight of vulcanizing agent, and 2.2 to 2.5 parts by weight of vulcanization accelerator.
2. In paragraph 1, A marine rubber packing composition suitable for polar environments, characterized by having excellent low-temperature flexibility and hydrostatic tightness, wherein the NBR is an NBR with an acrylonitrile content of 18%.
3. In paragraph 1, A marine rubber packing composition suitable for polar environments with excellent low-temperature flexibility and hydrostatic tightness, characterized in that the above-mentioned acetylene black is used after surface modification, and the modifying agent is hydrochloric acid, nitric acid, sulfuric acid, or chlorosulfuric acid.

Description

Rubber packing composition for ship with excellent low-temperature flexibility and water-pressure tightness suitable for polar environments The present invention relates to a rubber packing composition for ships that has cryogenic flexibility due to having a low glass transition temperature, while simultaneously increasing the crosslinking density to minimize the reduction in elasticity and improve durability and hydrostatic tightness. Icebreakers, which are essential for operations in extremely low (-55℃) environments, are a general term for ships that navigate while breaking ice. Typically, icebreakers play a role in clearing a route for other general merchant ships in frozen areas where navigation is impossible. Examples include icebreaking LNG carriers that transport crude oil in the Arctic Ocean, where an icebreaker leads by breaking the ice and an oil tanker follows behind. Unlike general-purpose vessels, ships operating in such cryogenic environments require packing materials, such as various gaskets and sealing materials, to lose their functionality due to cold ambient temperatures when cold fluids flow through the cold air and equipment, which can lead to equipment failure and large-scale environmental pollution. Therefore, rubber packing materials used in cryogenic environments require sufficient cold resistance and oil resistance. Therefore, packing materials for extreme environments are rubber-based composite materials requiring high functionality, such as elasticity, durability, and cold resistance even at cryogenic temperatures. It is essential to overcome the limitations of general rubber-based packing materials, where high hardness typically leads to excellent cold resistance but reduced durability due to lower elasticity. By possessing properties of low hardness and high elasticity, these materials must achieve performance that ensures excellent durability while maintaining high low-temperature flexibility even at cryogenic temperatures. In particular, cryogenic packing materials are high-performance materials capable of long-term use within a temperature range of around -50°C. Recently, their application fields have expanded, and they are widely utilized not only in LNG vessels but also in the military, space, aviation, and transportation sectors. However, domestic technology is focused solely on the manufacturing technology for LNG vessel equipment, and the packing materials used in this field are entirely dependent on imports. Meanwhile, high elasticity, wear resistance, and cold resistance are essential for such packing materials, and depending on the application, oil resistance, chemical resistance, and chemical resistance are required. Currently, the most widely used rubber material for packing is the NBR-based packing material as described in Patent Document 1. However, general NBR-based packing materials are copolymerized with butadiene, a polar monomer called acrylonitrile, and while they have excellent oil resistance and durability, there is a problem in that the glass transition temperature (Tg) rises and rebound elasticity and low-temperature flexibility decrease as the acrylonitrile content increases. In addition, due to the characteristics of rubber materials, phase transitions occur below Tg, causing the rubber to lose its inherent elasticity and potentially leading to reduced packing performance or failure under load; therefore, to address this, plasticizers were previously added or NBR with a low Tg was used. However, when a plasticizer is used in rubber materials, the Tg can be lowered, but since the plasticizer forcibly expands the molecular chains of the rubber material and lowers the bond energy, there is a problem of reduced heat resistance and oil resistance and deterioration of physical properties caused by the plasticizer. The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but will be implemented in various different forms. The embodiments described in this specification are provided to ensure that the disclosure of the invention is complete and to fully inform those skilled in the art of the scope of the invention. And the present invention is defined only by the scope of the claims. Accordingly, in some embodiments, well-known components, well-known operations, and well-known techniques are not specifically described to avoid the invention being interpreted ambiguously. Additionally, throughout the specification, the same reference numerals refer to the same components, and the terms used (mentioned) in this specification are for describing embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text, and components and oper