KR101141354B1 - Crome-based mixed catalyst for olefin polymerization - Google Patents
Crome-based mixed catalyst for olefin polymerization Download PDFInfo
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Abstract
본 발명은 올레핀 중합용 크롬계 혼합 촉매에 관한 것으로, 보다 상세하게는 실리카-티타니아-크로미아 터겔(tergels) 촉매 20 내지 80 중량%와 실리카-크로미아 코겔(cogels) 촉매 80 내지 20 중량%가 혼합되어 이루어지되, 상기 터겔 촉매는 티탄(Ti) 함량이 0.5 내지 3 중량%이고, 크롬(Cr) 함량이 0.5 내지 2.0 중량%이며, 상기 코겔 촉매는 크롬(Cr) 함량이 0.5 내지 2.0 중량%인 것을 특징으로 하는 올레핀 중합용 크롬계 혼합 촉매에 관한 것이다. The present invention relates to a chromium-based mixed catalyst for olefin polymerization, more specifically, 20 to 80% by weight of silica-titania-chromia tergels catalyst and 80 to 20% by weight of silica-chromia cogels catalyst The tergel catalyst has a titanium content of 0.5 to 3 wt%, a chromium (Cr) content of 0.5 to 2.0 wt%, and the cogel catalyst has a chromium (Cr) content of 0.5 to 2.0 wt%. The present invention relates to a chromium-based mixed catalyst for olefin polymerization.
본 발명에 따른 크롬계 혼합 촉매는, 고밀도 폴리올레핀의 제품 중 모노 필라멘트(mono-filament)와 얀(yarn) 성형 수지에 적용되는 것으로서 특히, 얀(yarn) 성형 수지에 대한 것이며, 올레핀 중합 반응에 의해 생성되는 고밀도 폴리올레핀의 기계적 물성 및 성형 가공성을 향상시키는 효과가 있다.The chromium-based mixed catalyst according to the present invention is applied to mono-filament and yarn molding resins of a high-density polyolefin product, and particularly to yarn molding resins. There is an effect of improving the mechanical properties and molding processability of the resulting high density polyolefin.
크롬계 촉매, 혼합 촉매, 폴리올레핀, 폴리에틸렌, 모노필라멘트, 얀, 성형 가공성 Chromium-based catalysts, mixed catalysts, polyolefins, polyethylene, monofilaments, yarns, molding processability
Description
본 발명은 올레핀 중합용 크롬계 혼합 촉매에 관한 것으로, 보다 상세하게는 올레핀 중합 반응에 사용되는 서로 다른 두 개의 크롬계 촉매가 혼합된 크롬계 혼합 촉매에 관한 것이다. The present invention relates to a chromium-based mixed catalyst for olefin polymerization, and more particularly to a chromium-based mixed catalyst in which two different chromium-based catalysts used in the olefin polymerization reaction are mixed.
올레핀 중합용 크롬계 촉매는 1950년대 초, Phillips 연구소의 J.Paul Hogan과 Robert L. Banks에 의해 처음 개발되었으며, 현재 다양한 형태의 크롬계 촉매가 중합공정에 이용되고 있다. Chromium-based catalysts for olefin polymerization were first developed in the early 1950's by J. Paul Hogan and Robert L. Banks of Phillips Laboratories. Currently, various types of chromium-based catalysts are used in the polymerization process.
상기 크롬계 촉매는 지글러-나타(Ziegler-natta)계 촉매와 달리 반응기 투입전 650~850 ℃의 뜨거운 공기에 의한 활성화(activation)가 필요한데, 850 ℃를 초과하는 경우에는 실리카 구조의 붕괴로 촉매 표면적이 감소하는 소결(sintering)현상이 발생하여 촉매의 활성(activity)이 떨어지는 문제가 있다. Unlike the Ziegler-Natta catalyst, the chromium-based catalyst requires activation by hot air at 650 ° C. to 850 ° C. before the reactor is introduced. This decrease in sintering (sintering) occurs, there is a problem that the activity of the catalyst (active) falls.
또한, 상기 크롬계 촉매는 반응기 내에서 중합개시 전 5분 내지 1시간의 유 도시간(induction time, 산화수 6가에서 2가로 전환되는데 필요한 시간)을 가지며, 고분자의 MI(melt index)는 수소농도가 아닌 반응기 온도로 제어된다. In addition, the chromium-based catalyst has an induction time of 5 minutes to 1 hour before the start of polymerization in the reactor (time required to convert from hexavalent oxide to divalent), and the polymer MI (melt index) is hydrogen concentration. Controlled by the reactor temperature.
상기 촉매를 활성화 시킨 후 일산화가스(CO)로 환원시킴으로써 유도시간을 없애고, 중합율을 증가시키는 효과를 얻을 수도 있으나, 일산화 탄소가 촉매 활성점에 화학적으로 흡착되어 촉매의 활성(activity)을 감소시키는 문제점이 있다. By activating the catalyst and reducing it to CO, it is possible to eliminate the induction time and increase the polymerization rate, but carbon monoxide is chemically adsorbed at the catalyst active point to reduce the activity of the catalyst. There is a problem.
본 발명에서는 혼합촉매 조성물을 이용하여 개선된 물성의 폴리 올레핀을 제조하는 방법에 관한 것이다.The present invention relates to a process for preparing polyolefins of improved physical properties using mixed catalyst compositions.
상기와 같은 종래기술의 문제점을 해결하고자, 본 발명은 기계적 물성 및 성형 가공성이 우수하고, 고밀도 폴리올레핀의 제품 중 모노 필라멘트(mono-filament)와 얀(yarn) 성형수지에 적합한 올레핀 중합용 크롬계 혼합 촉매를 제공하는 것을 목적으로 한다. In order to solve the problems of the prior art as described above, the present invention has excellent mechanical properties and molding processability, chromium-based mixture for olefin polymerization suitable for mono-filament and yarn molding resin of the product of high density polyolefin It is an object to provide a catalyst.
또한 본 발명은 상기 올레핀 중합용 크롬계 혼합 촉매에 의하여 제조된 모노 필라멘트(mono-filament) 및 얀(yarn) 성형수지용 폴리올레핀을 제공하는 것을 목적으로 한다. It is another object of the present invention to provide a polyolefin for monofilament and yarn molding resin prepared by the chromium-based mixed catalyst for olefin polymerization.
본 발명의 상기 목적 및 기타 목적들은 하기 설명된 본 발명에 의하여 모두 달성될 수 있다.These and other objects of the present invention can be achieved by the present invention described below.
상기의 목적을 달성하기 위하여, 본 발명은 실리카-티타니아-크로미아 터겔(tergels) 촉매 20 내지 80 중량%와 실리카-크로미아 코겔(cogels) 촉매 80 내지 20 중량%가 혼합되어 이루어지되, 상기 터겔 촉매는 티탄(Ti) 함량이 0.5 내지 3 중량%이고, 크롬(Cr) 함량이 0.5 내지 2.0 중량%이며, 상기 코겔 촉매는 크롬(Cr) 함량이 0.5 내지 2.0 중량%인 것을 특징으로 하는 올레핀 중합용 크롬계 혼합 촉매를 제공한다.In order to achieve the above object, the present invention is made by mixing 20 to 80% by weight of silica-titania-chromia tergels catalyst and 80 to 20% by weight of silica-chromia cogels catalyst, the tergel The catalyst is an olefin polymerization, characterized in that the titanium (Ti) content of 0.5 to 3% by weight, the chromium (Cr) content is 0.5 to 2.0% by weight, and the cogel catalyst has a chromium (Cr) content of 0.5 to 2.0% by weight. A chromium-based mixed catalyst is provided.
또한, 본 발명은 상기 올레핀 중합용 크롬계 혼합 촉매에 의하여 제조된 모 노 필라멘트(mono-filament) 및 얀(yarn) 성형수지용 폴리올레핀을 제공한다.The present invention also provides a polyolefin for mono-filament and yarn molding resin produced by the chromium-based mixed catalyst for olefin polymerization.
상기에서 살펴본 바와 같이, 본 발명에 따르면 모노 필라멘트(mono-filament)와 얀(yarn) 성형 수지의 적용에 적합하고, 기계적 물성 및 성형 가공성이 우수한 고밀도 폴리올레핀을 제조할 수 있는 크롬계 혼합 촉매 및 이에 의하여 제조된 폴리올레핀을 제공하는 효과가 있다.As described above, according to the present invention, a chromium-based mixed catalyst suitable for application of mono-filament and yarn molding resin and capable of producing a high density polyolefin having excellent mechanical properties and molding processability, and thus There is an effect to provide a polyolefin produced by.
이하 본 발명을 상세하게 설명한다. Hereinafter, the present invention will be described in detail.
본 발명의 올레핀 중합용 크롬계 혼합 촉매는 실리카-티타니아-크로미아 터겔(tergels) 촉매 20 내지 80 중량%와 실리카-크로미아 코겔(cogels) 촉매 80 내지 20 중량%가 혼합되어 이루어지되, 상기 터겔 촉매는 티탄(Ti) 함량이 0.5 내지 3 중량%이고, 크롬(Cr) 함량이 0.5 내지 2.0 중량%이며, 상기 코겔 촉매는 크롬(Cr) 함량이 0.5 내지 2.0 중량%인 것을 특징으로 한다.The chromium-based mixed catalyst for olefin polymerization of the present invention is made by mixing 20 to 80% by weight of silica-titania-chromia tergels catalyst and 80 to 20% by weight of silica-chromia cogels catalyst. The catalyst is titanium (Ti) content of 0.5 to 3% by weight, chromium (Cr) content is 0.5 to 2.0% by weight, the cogel catalyst is characterized in that the chromium (Cr) content is 0.5 to 2.0% by weight.
상기 코겔 촉매는 그 표면에 티탄(Ti)을 1.0 내지 2.5 중량%로 더 포함할 수 있는 것을 특징으로 한다.The cogel catalyst is characterized in that it may further comprise titanium (Ti) in the 1.0 to 2.5% by weight on the surface.
상기 터겔 촉매는 650 내지 850 ℃에서 4 내지 8 시간 소성시켜 활성화시키고, 상기 코겔 촉매는 650 내지 850 ℃에서 6 내지 10 시간 소성시켜 활성화시킨 후 혼합 사용 하였다.The tergel catalyst was activated by firing at 650 to 850 ° C. for 4 to 8 hours, and the cogel catalyst was activated by firing at 650 to 850 ° C. for 6 to 10 hours and then mixed.
상기 올레핀은 에틸렌인 것이 바람직하다.It is preferable that the said olefin is ethylene.
본 발명의 모노 필라멘트(mono-filament) 및 얀(yarn) 성형수지용 폴리올레핀은 상기 올레핀 중합용 크롬계 혼합 촉매에 의하여 제조되는 것을 특징으로 한다.The polyolefin for mono-filament and yarn molding resin of the present invention is characterized by being produced by the chromium-based mixed catalyst for olefin polymerization.
상기 폴리올레핀은 다분산성 지수(polydispersity index)를 나타내는 Mw(중량평균분자량)/Mn(수평균분자량)의 값이 15 내지 20일 수 있다. The polyolefin may have a value of Mw (weight average molecular weight) / Mn (number average molecular weight) representing a polydispersity index.
상기 다분산성 지수는 고분자 수지의 분자량 분포를 나타내는 기준이 되는데, 그 값이 증가하게 되면 고분자 수지의 분자량 분포가 커지게 되고 가공성이 증가한다.The polydispersity index serves as a criterion indicating the molecular weight distribution of the polymer resin, and when the value thereof is increased, the molecular weight distribution of the polymer resin is increased and the processability is increased.
상기 폴리올레핀은 모노 필라멘트(mono-filament) 및 얀(yarn) 성형수지에 적용되는 것이 바람직하고, 특히 바람직하게는 얀(yarn) 성형수지에 적용되는 것이다.The polyolefin is preferably applied to mono-filament and yarn molding resin, and particularly preferably to yarn molding resin.
이하, 본 발명의 이해를 돕기 위하여 바람직한 실시예를 제시하나, 하기 실시예는 본 발명을 예시하는 것일 뿐 본 발명의 범위가 하기 실시예에 한정되는 것은 아니다.Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited to the following examples.
[실시예][Example]
실시예 1Example 1
실리카-티타니아-크로미아 터겔 촉매(Magnapore 963, Grace사)를 공기를 사용하여 695 ℃의 온도에서 6 시간 소성시켜 활성화시키고, 실리카-크로미아 코겔 촉매(촉매표면 Cr 0.91 wt%)를 공기를 사용하여 700 ℃의 온도에서 8 시간 소성시켜 활성화시켰다. 활성화된 상기 터겔 촉매 75 중량%와 상기 코겔 촉매 25 중량%를 혼합하여 크롬계 혼합 촉매를 제조하였다. The silica-titania-chromia tergel catalyst (Magnapore 963, Grace) was activated by firing at a temperature of 695 ° C. for 6 hours using air, and the silica-chromia cogel catalyst (catalyst surface Cr 0.91 wt%) was used for air. It was activated by firing at a temperature of 700 ℃ for 8 hours. 75 wt% of the activated tergel catalyst and 25 wt% of the cogel catalyst were mixed to prepare a chromium-based mixed catalyst.
상기 크롬계 혼합 촉매와 에틸렌 단량체를 이소부탄 용매 하에서 반응온도 94 내지 99 ℃, 반응압력 600 psi, 에틸렌 유량 24 내지 28 kg/hr, 반응시간은 리싸이클 이소부탄을 기준으로 약 2 시간 조건으로 중합 반응하여 폴리에틸렌 수지를 제조하였다The chromium-based mixed catalyst and the ethylene monomer were reacted under an isobutane solvent at a reaction temperature of 94 to 99 ° C., a reaction pressure of 600 psi, an ethylene flow rate of 24 to 28 kg / hr, and a reaction time of about 2 hours based on recycle isobutane. Polyethylene resin was prepared.
실시예 2Example 2
상기 실시예 1에서 터겔 촉매 50 중량%와 코겔 촉매 50 중량%를 사용한 것을 제외하고는 상기 실시예 1과 동일한 방법으로 실시하였다. Except that 50 wt% of the tergel catalyst and 50 wt% of the cogel catalyst in Example 1 was carried out in the same manner as in Example 1.
실시예 3Example 3
상기 실시예 1에서 터겔 촉매 25 중량%와 코겔 촉매 75 중량%를 사용한 것을 제외하고는 상기 실시예 1과 동일한 방법으로 실시하였다. Except that 25 wt% of the tergel catalyst and 75 wt% of the cogel catalyst in Example 1 was carried out in the same manner as in Example 1.
비교예 1Comparative Example 1
상기 실시예 1에서 코겔 촉매를 사용하지 않은 것을 제외하고는 상기 실시예 1과 동일한 방법으로 실시하였다. Except that the cogel catalyst was not used in Example 1 was carried out in the same manner as in Example 1.
비교예 2Comparative Example 2
상기 실시예 1에서 터겔 촉매를 사용하지 않은 것을 제외하고는 상기 실시예 1과 동일한 방법으로 실시하였다.Except that the tergel catalyst was not used in Example 1 was carried out in the same manner as in Example 1.
[시험예][Test Example]
상기 실시예 1 내지 3 및 비교예 1, 2에서 제조된 폴리에틸렌의 특성을 하기의 방법으로 측정하고, 그 결과를 하기의 표 1에 나타내었다.The properties of the polyethylene prepared in Examples 1 to 3 and Comparative Examples 1 and 2 were measured by the following method, and the results are shown in Table 1 below.
* 인열강도(Tear Strength)- ASTM D1922에 의거하여 측정하였다.* Tear Strength-measured according to ASTM D1922.
* 인장강도(Tensile Strength)- ASTM에 의거하여 측정하였다.Tensile Strength-Measured according to ASTM.
구분
division
터겔
촉매
Tergel
catalyst
코겔
촉매
Cogel
catalyst
Melt
Index
Melt
Index
다분산성지수
(Mw/Mn)
Polydispersity Index
(Mw / Mn)
(kg/cm2)The tensile strength
(kg / cm 2 )
(kg/cm)Phosphorus strength
(kg / cm)
종방향MD
Longitudinal direction
횡방향TD
Transverse
종방향MD
Longitudinal direction
횡방향TD
Transverse
상기 표 1에 나타낸 바와 같이, 본 발명에 따른 폴리올레핀(실시예 1 내지 3)은 실리카-티타니아-크로미아 터겔 촉매 또는 실리카-크로미아 코겔 촉매만을 사용하여 제조된 폴리올레핀(비교예 1, 2)에 비하여 다분산성 지수(가공성), 인장강도 및 인열강도가 모두 우수함을 확인할 수 있었다.As shown in Table 1, the polyolefins (Examples 1 to 3) according to the present invention are prepared in polyolefins (Comparative Examples 1 and 2) prepared using only a silica-titania-chromia tergel catalyst or a silica-chromia cogel catalyst. In comparison, polydispersity index (processability), tensile strength and tear strength were all excellent.
Claims (4)
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Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4547557A (en) * | 1984-07-09 | 1985-10-15 | Phillips Petroleum Company | Silica-titania cogel from two-step hydrolysis |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4547557A (en) * | 1984-07-09 | 1985-10-15 | Phillips Petroleum Company | Silica-titania cogel from two-step hydrolysis |
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